Electrolysis

Today I'm going to talk about electrolysis, the final thing that you need to learn about redox in Year 11 Chemistry.

Remember how I said that sometimes reactions might not occur, depending on where the elements sit on the Standard Reduction Potentials chart? (See Redox Equations if you can't remember.) Well, I lied (or at least I think I did...). It is possible to make these reactions occur, but they won't occur spontaneously. That's where electrolysis comes in- an electrical current is passed through a substance to make a reaction occur. For example, you can electrolyse sodium chloride to give you sodium and chlorine, and I'm pretty sure you can also electrolyse water to give hydrogen and oxygen.

To electrolyse something, you need some equipment: mainly a battery, some wires, and inert substances such as graphite. Oh, and you also need the solution that you want to electrolyse. The solution is known as the electrolyte while the inert substances are the electrodes.(You can have electrodes that aren't made of inert substances, but if they aren't inert then they might react in the electrolysis process. Sometimes this comes in handy, like in electroplating which I'll tell you about in a future post, but most other times you'll want to keep the electrodes inert.)

Here's a nice little diagram of how to set up the equipment:

Now, the way I think this works is that the battery provides electrons for oxidation and reduction processes to occur. Electrons flow through the battery from the positive end to the negative end, then out the negative end into the rest of the circuit, then back up the positive end. Therefore, electrons are flowing into the electrode known as the cathode, making the cathode negatively charged, and flowing out of the electrode known as the anode, making the anode positively charged. Because of this, positively- and negatively- charged ions flow to the cathode and the anode, respectively.

How will I remember all this?! you might ask. Well, you could try my Chemistry teacher's trick. The anode is positive because it starts with an A and getting an A+ is a really good thing, while the cathode is negative because it starts with a C and that's just average. Also you might find it interesting (though not really that helpful) that positive ions, also known as cations, flow to the cathode, while negative ions, also known as anions, flow to the anode. There's also another acronym that might help you remember stuff:

AN OIL RIG CAT
At the Anode, Oxidation, which Is Loss takes place while Reduction which Is Gain takes place at the Cathode.

Writing half-equations for electrolysis of molten salts is the same as writing half-equations anywhere else (see Redox Equations for more info). If you're using solutions, however, things get a bit trickier, as a solution indicates that water comes into it as well. In this case, you need to write down all of the possible oxidation reactions and all of the possible reduction reactions. FYI, here are the oxidation and reduction reactions for water:

Oxidation: 2H₂O -> O₂ + 4H⁺ + 4e^-

Reduction: 2H₂O + 2e^- -> H₂ + 2OH^-

(By the way, Wikipedia pointed out to me that if you combine these two equations you get 2H₂O -> H₂ + O_{2 : the electrolysis of water.)}

Then you need to go back to the good ol' Standard Reduction Potentials table and look at those numbers on the side. Compare the standard reduction potentials of the two elements that might possibly be oxidised/ reduced. The element you need is the one with the highest standard reduction potential. (Be careful, though, as some of the reactions might be listed the other way around on your sheet. If this is the case, then you need to change the sign on the standard reduction potential value from positive to negative or vice versa. It may be easier just to look for the highest absolute value.)

(Actually I need to double check that last paragraph- this is the section where I get all confused with what's what. I'm sure it's not that confusing. One day I'll sort it out... though I can get some consolation from the fact that solutions isn't strictly required knowledge in Chemistry 2AB...)

How to Deal with Qualified Drivers

Qualified Drivers- the bane of every Learner Driver. Some qualified drivers are retards, but I get the feeling that many learners who hate the qualified drivers (hereafter referred to as Q-drivers) tend to hate them just because they're there. I've decided to write this guide to combat the average learner's fear (for lack of a better word) of Q-drivers. After all, being able to handle traffic is all part of being a driver- and yes, that means being able to handle the fact that there are other Q-drivers around and some of them are pretty nasty towards L-drivers.

Q-drivers come in all different varieties. There's the nice ones and the indifferent ones, the tailgaters and the show-offs. And yes, there's the smart Q-drivers and the idiotic Q-drivers. Just because you have your driver's licence doesn't mean that you're a smart, safe, courteous driver. Conversely, just because you're still on your Ls doesn't mean that you're a dumb, dangerous, discourteous driver. L-drivers have as much right to be on the road as Q-drivers do, provided that they have L-plates, their learner's permits and a supervisor. I'm going to repeat that again, just to stress my point: you have as much right to be on the road as any Q-driver, so you deserve to be afforded the same amount of respect and courtesy as a Q-driver. Don't let other people's attitudes get in your way of becoming good at driving.

One thing that I found really helped me in becoming used to other Q-drivers is by pretending that I am one- one that follows the road rules, anyway. Since I got into this frame of mind, other benefits compounded on this. I've been beeped at a couple of times by impatient drivers, but because I don't see myself as that L-driver that all of the Q-drivers hate, I just go, "bloody impatient driver" and go on my merry way. Of course, this tactic might not work for you as everyone's mind is different.

If you get a tailgater, you could try some of the tactics that I've gathered from Q-drivers. (However, if you try one of these, you should be sure that the driver behind is definitely a tailgater and that it isn't a case of the car just appearing to be close when you look at it in the rearview mirror.) Here are some tactics:

1. Tap the brake pedal not so much that you start slowing down, but enough so that the brake lights come on.
2. Let go of the accelerate pedal.
3. Use the windscreen spray thingo. If the wind's right the water might blow onto their windscreen. My mum did this on the freeway to a jerk who was tailgating her...
4. If there's an intersection nearby, indicate so that they think that you're turning and will slow down to allow you to turn.
5. If there's a place where they can overtake, slow down to allow them to overtake. However, tailgaters will probably overtake on their own as soon as they have the opportunity to do so.
6. You could always simply ignore the tailgater. Or you could pull faces at them in your rearview mirror. Whatever.

Whatever you do, though, NEVER NEVER NEVER go over the speed limit just to appease a Q-driver. If there's a camera nearby, it's you who'll end up with the fine, not them.

And that's pretty much it for my article on how to handle Q-drivers. If you're still struggling you could try and drive an automatic so that you don't have to worry about Q-drivers and gears at the same time. I'll have to admit that I'm learning on automatic (both my parents have automatics) so I don't have any advice for you if you stall your car in the midst of a whole bunch of Q-drivers. I can, however, offer some consolation: the Q-driver in front of me stalled their car at an intersection. If Q-drivers can stall their cars then really there's nothing that hateful about L-drivers stalling their cars either.

As always, if you have anything else to say on the matter, please leave a comment!

How to Turn Left

Hiya all, today I'm going to post about driving.

When you start learning how to drive, even the simplest little tasks like turning left and right can seem daunting, so I've composed a nice little guide on how to turn left.

First of all, your preparation is pretty important. You should slow down as much as possible before you turn as it is easier to control your car at a lower speed. As my driving instructor says, cars are like men: they can only do one thing at a time. They can slow down, or they can turn, but they can't really do both at the same time, so make sure you do most of your slowing down before you get to the road you want to turn into. 15-25km/h is a good speed for turning at, less if it's raining.

When you turn left, the position of your car is also important. Most suburbian roads widen out at the end for a reason, and that reason is to help you turn left! Make full use of that curvy bit to help you turn. Here's a diagram (I even labelled the car for you, hehe):

The trick is that, to get in this position in the first place, you would already have had to have put some turn on the wheel. That way, when you actually make the turn, you don't have to turn the wheel much more.

Of course there are some roads that won't enable you to do this, but most of the time you can get a nice left-hand turn position going. Even when you're not turning left at the end of the road but down some other random road instead, you'll still find that there are curvy bits where the roads intersect and you can use these to your advantage.

I have another tip for you and that is in regards to steering. If you find that you can't steer sharply enough, try this steering method. To turn left, grab the top of the wheel with your left hand and pull anticlockwise. Push up anticlockwise with your right hand. Repeat the process as needed. To turn right, just reverse the directions.

To sum up- here are the steps that you should be taking when you do a left-hand turn on a normal suburban road:

1. Check your mirrors
2. Start slowing down
3. As you slow down, indicate that you're about to turn left.
4. Get into the left-hand turning position.
5. If you're on a terminating road about to enter a different road, you need to stop and check for traffic in the left lane. If it's all clear, then you can go.

By the way, if visibility is good, as in REALLY good and you can see for quite a while down the road, and you can see that there aren't any cars coming, then you don't need to stop completely at the end of a terminating road unless there's a stop sign. (You must stop before stop signs- even if you're stopped behind a car stopped at a stop sign, once that car moves off, you need to stop AGAIN at the stop sign BEFORE you move off. I learned this the hard way with my driving instructor- at least I didn't learn the hard hard way in a driving test...)

Hopefully that helps you all with turning left... if anyone has any other tips, or if there's anything incorrect in this post, let me know!

Radicals 足 刀 日

I said I was going to post 3 a day, but I kind of didn't stick to that promise. Ah well.

Here are 3 more radicals for you to learn today.

足， ⻊ = foot

This character exists as a standalone character, but it has a slightly different form that appears on the left hand side of some characters, particularly those to do with feet.

足 - foot
跑 - run
踢 - kick (踢足球 - play football/soccer)
跃 - leap, jump
蹦 - leap, jump, spring
跳 - leap, jump, spring, bounce (the list of English translations keeps growing...)
跟 - with, to follow
踩 - step on, trample

刀，刂 = sword, knife

One way of remembering that the two characters are related is that the second one is really just the first one with the top bit removed and the left bit squished a bit closer towards the right bit- wait, that wasn't really all too helpful... There's also a third form that I don't know how to type and can't find one that I can copy or paste (though to be honest I'm not really looking very hard). It looks like the top of the character 色 or 龟.

刀 - sword, knife
剪 - scissors, shears
色 - colour
龟 - turtle
兔 - rabbit
划 - stroke (of a Chinese character), to scratch
切 - cut
免 - avoid, avert, escape (免费 - free of charge)
刚 - just
别 - other, don't

日 - sun, day

This character evolved from a pictograph. I'm sure you can find its origins on a quick Google search.

日 - sun, day
旧 - old
旦 - dawn
晓 - dawn, daybreak
显 - apparent, obvious, show, display, illustrious and influential
明 - bright (昆明 - Kunming, capital of Yunnan Province in China, which is where the Hanyu Qiao Chinese Proficiency Competition is going to be held this year)
时 - time
旭 - rising sun
早 - early, morning
晚 - night
量 - to measure
晴 - sunny

Redox equations

This is possibly the reason why I hate redox so much. The actual equations themselves aren't too bad, it's just working out whether a reaction occurs or not. My brain always gets mixed up reading that stupid reduction potentials chart... argh...

Anyway. The first two types of redox reactions that I'm going to talk about are metal and halogen displacement reactions.

In metal displacement reactions, a metal reacts with a metal ion in such a way that the originally solid metal becomes an ion and the original metal ion becomes a solid metal. Confused yet?

For example, if you have solid potassium reacting with a solution of sodium chloride (i.e. sodium ions and chloride ions), you'd end up with solid sodium and a solution of potassium chloride (i.e. potassium ions and chloride ions). The net ionic equation would look like this:

K + Na⁺-> Na + K⁺

In this reaction, K has been oxidised and Na has been reduced.

Note that if you had solid sodium and a solution of potassium chloride, they would not react. But how can you tell just by looking at the reactants if you're going to have a reaction or not? This is where the Standard Reduction Potentials table at the back of your data sheet comes in.

The closer an element is to the bottom of the table, the more it wants to be oxidised and become a positive ion. For the most part, groups I and II elements (alkali metals and alkaline earth metals) are at the very bottom and directly above them is mainly transition elements (with exceptions such as aluminium and water which randomly snuck in). I'm very curious as to why this is so, but I'm too lazy to look it up myself.

When you have the reactants of a metal displacement reaction, take a look at the Standard Reduction Potentials chart. Which element has the strongest desire to be a positive ion? If it's already a positive ion, no reaction will occur. If it isn't, then a reaction will occur. That's basically how it works.

Halogen displacement reactions are the opposite of metal displacement reactions. Here's an example:

F₂ + 2Br^- -> 2F^- + Br₂

Now, when working out whether a reaction will occur or not, you have to do the opposite of what you did with the metal displacement reactions as this time we're dealing with negative ions, not positive ones.

If the bottom of the table lists the elements that want to be oxidised and become positive ions, then it also follows that the top of the table lists the elements that want to be reduced to negative ions. When working out halogen displacement reactions, work out which element has the strongest desire to be a negative ion. Then think about whether that element is already a negative ion or not. If it's already a negative ion, then no reaction will occur. If not, then a reaction will occur.

(By the way, there are ways to force the reactants to react even when they don't really want to, but I'm not going to go into that for now.)

Now, next up is half equations. In Chemistry 2AB, you only have to deal with the dead easy half equations, but there's also acidic conditions and stuff that you can learn about too.

You can write half equations for any kind of redox reaction, whether it be metal displacement, halogen displacement, or a myriad of other types of reactions that I don't know the names of. As long as an element is being reduced and another is being oxidised, you can write half equations.

Basically, you write separate equations for the reductant and the oxidant. Then you add in electrons to balance the charges.

F₂ + 2e^- -> 2F^- 

2Br^- -> Br_{2 +} 2e^-

Just make sure that the number of Fs or Brs or whatever are balanced on either side of the equation, and then chuck in some electrons to balance the charges as well.

You can also write balanced net ionic equations as well simply by adding together the two half-equations and then cancelling off the electrons on either side. If the two half-equations involve different numbers of electrons, however, care needs to be taken.

If you have different numbers of electrons in the two equations, what you first need to do is multiply each by a certain number so that the number of electrons are the same. For example, if you have 3 electrons in the first equation and 2 in the second, you can multiply the first equation by 2 and the second by 3 so that you have 6 electrons in both equations. Then you can add the two equations together, cancelling out the electrons on both sides. It's just like simultaneous equations in maths really.

Earlier, I mentioned half equations in acidic conditions. Normally, when you have a question asking for these, it's because you have some crazy polyatomic ion like the chromate ion. The steps for working out these are as follows:

1. Balance the number of atoms on each side (except for hydrogen and oxygen- we'll get to them later).

MnO₄^- -> Mn²⁺

2. Add water in order to balance out the number of oxygen atoms.

MnO₄^- -> Mn²⁺ + 4H₂O

3. Add hydrogen ions (acidic conditions, remember?) to balance out the number of hydrogen atoms.

MnO₄^- + 8H⁺ -> Mn²⁺ + 4H₂O

4. Calculate overall charge on each side.

In above equation, the left hand side has an overall charge of +7 while the right hand side has an overall charge of +2.

5. Add electrons to balance out the charges.

MnO₄^- + 8H⁺ + 5e^- -> Mn²⁺ + 4H₂O

So that's pretty much all you need to know and more on redox equations! Next up- electrolysis!

Basics of Redox

Argh I hate redox. I'm not too bad at it, but it annoys me for some reason. Anyway, rant over, it's time for me to try and explain it.

Now, redox is all about the transfer of electrons. When an atom gains electrons and thus has its charge reduced, we say that it has undergone reduction. When an atom loses electrons, we say that it has undergone oxidation. The word "oxidation" comes from the fact that there are lots of cases in which the addition of oxygen makes another atom lose electrons.

When do redox reactions occur? Well, you know very well that the transfer of electrons happens when atoms become ions. (If you didn't already know this, go here to find out more.) But there are other times when electrons are transferred too. It's easier to explain this by talking about oxidation numbers, so that's what I'm going to talk about first.

You can assign each element in a compound an oxidation number. If it's just a single element you're looking at, like Fe or O2 or Na, the oxidation number is 0. Hydrogen usually has an oxidation number of +1, but if it's a metal hydride, then it has an oxidation number of -1. (And, as said before, if it's on its own, like in H2, then it has an oxidation number of 0.) Similarly, oxygen usually has an oxidation number of -2, but there are a few exceptions where this is different (I'll have to check what the exceptions are). In ionically-bonded compounds, the oxidation number of each monoatomic ion (ion with only one atom (ion?), like Na+) is simply the charge on the ion (for example, the oxidation number of Na in NaCl is +1 because Na has a +1 charge). Assign these elements their oxidation numbers first.

Now, in a neutrally-charged compound, all of the oxidation numbers have to add to 0. Similarly, in a charged compound or polyatomic ion, all of the oxidation numbers have to add to the charge on the ion or compound. Simple, isn't it?

Now I'm going to talk about carbonic acid, H2CO3. Let's start off by assigning it some oxidation numbers.

Since this isn't a metal hydride, the oxidation number of H is +1. That was easy, wasn't it?

Now, CO₃<sup>2- has a -2 charge. Therefore, the oxidation numbers of C and O need to add up to -2. Each O has an oxidation number of -2. Three Os have a combined oxidation number of -6. C must have an oxidation number of 4 because 4-6 = -2, the overall charge on the ion.

That wasn't too hard, was it? (If it was, don't feel stupid, just ask me to clarify.) Now for two more examples: carbon dioxide and water.

Water's easy. Each H has an oxidation number of +1 (the two Hs combined have an oxidation number of +2) and O has an oxidation number of -2. The overall charge is 0.

Carbon dioxide isn't much harder. Each O has an oxidation number of -2, and because carbon dioxide is neutral, the oxidation number of C has to balance out the oxidation number of the Os. The oxidation number of C is therefore 4.

Now, the decomposition reaction of carbonic acid to carbon dioxide and water is not a redox reaction. Why? Well, it's because none of the elements has changed oxidation number! If any of the elements had changed oxidation number, then it would be a redox reaction. (Sorry, I thought this decomposition reaction would be a redox reaction as well, but soon realised that it wasn't. One day I'll put a better example up.)

In a redox reaction...

The element that loses electrons, thereby obtaining a higher oxidation number, has been oxidised and is known as the reducing agent or reductant (as it reduces the other element).

The element that gains electrons, thereby having its oxidation number reduced, has been reduced and is known as the oxidising agent or oxidant (as it oxidises the other element as it is being reduced).

Remember that if electrons are being lost then they have to have somewhere to go to, and vice versa (if electrons are being gained the atom needs to gain them from somewhere).</sup>

By the way, there's a nice little mnemonic to help you remember which is the oxidant and which is the reductant. It's OIL RIG. It stands for Oxidation Is Loss of electrons, Reduction Is Gain of electrons.

I'm too tired to do any more for now. At least I've done the first four dot points here (explain oxidation and reduction as electron transfer, calculate oxidation numbers, identify and name oxidants and reductants and identify redox reactions using oxidation numbers). I think I'm good for now. Only 5 dot points left and I'll have gone through pretty much the whole Chemistry 2AB course- unless you count all of the Applied Chemistry stuff, of course.

Naming and Drawing Organic Compounds

Because I'm pretty lazy, I just photocopied my Chemistry holiday homework for this one.

Sorry that it's on a slight angle.

Rightio, let's start with 1a. It's always a good place to start!

First things first- identifying which homologous series the structure belongs to. There's only single bonds here, so it's an alkane and will therefore end with an -ane ending.

Secondly, we work out what the longest carbon chain is. No, it's not 4, it's actually 6. There's three on the top row, and then the third one joins on to the three on the bottom row. (Due to the nature of single bonds, rotations and flips and whatnot don't change the order of bonding- sorry, couldn't think of a clearer term. Anyway, diagrams don't even accurately show where the atoms are in relation to each other.) Therefore, we know that there's a hex- in there somewhere. So far, we've got ourselves "hexane."

But what about that extra CH3 joined on to the third atom? Well, that's called a "alkyl group." Because there's only one C atom, it's "methyl-." (If there were two carbons, it'd be ethyl-. Three would make it propyl-, and so on.)

Now, we also have to assign the alkyl group a number so that we know where to find it on the chain! Counting in one direction, the alkyl group's on the 3rd carbon. Counting in the other direction, it's on the 4th carbon. Always work with the lower numbers. Since 3 is lower than 4, we'll stick with 3. Finally, since there's only one methyl group, we don't need to worry about adding di- or tri- before the "methyl." (You don't need to add mono- either- if there's no prefixes, it's implied that there's only one.) Therefore, the final name is 3-methylhexane. Yay!

We can write this all down as a series of steps:

1. Figure out which homologous series the structure belongs to. This will give the suffix.
2. Count the number of carbons in the longest carbon chain.
3. Figure out the names and locations of all attachments to the chain that aren't hydrogen atoms. (This includes alkyl groups and halogens like bromine and iodine.) If there's more than one of anything, indicate this with a prefix like di- or tri-. Also, when giving locations of groups, make sure to give all the attachments the lowest possible numbers. List all attachments in alphabetical order.

Let's try these steps with 1e.

Homologous series- Alkane, as all single bonds. Hence -ane ending.

No. of carbons- 10, so dec-.

Extra bits and pieces:

1 x Chlorine at 2

1 x Fluorine at 5

3 (tri-) x Methyl at 3, 3 and 9

1 x Propyl at 5

Final name: 2-chloro-5-fluoro-3,3,9-trimethyl-5-propyldecane

I won't give worked examples of the other ones because I have to wake up at 6am tomorrow and I'm not a morning person, but I will give some pointers.

NO2 goes by the prefix nitro- and NH2- goes by the prefix amino-. However, you don't really have to worry about these in 2AB Chemistry.

You also don't need to worry about cycloalkyl groups in 2AB (as seen in 3c). They work pretty much the same way as an alkyl group. The trick is knowing whether you're dealing with a cycloalkane with alkyl groups or an alkane with cycloalkyl groups.

You do need to worry about cycloalkanes with alkyl groups. Labelling these is exactly the same as labelling alkanes with alkyl groups. The only difference is that cycloalkanes obviously don't have ends. The numbering goes clockwise. Just try and make it so that each alkyl group or halogen has the lowest numbering possible. Halogens should get preference for the lowest numbers.

Now for drawing hydrocarbons. I'm going to pick a semi-hard example so that I'll cover pretty much everything and will only have to explain once. The example I'm going to pick is 2i: 2,2-dichloro-6-methyl-4-propylheptane.

Drawing hydrocarbons is easier, in my opinion. Here are my steps:

1. Draw all of the carbons required.

2. Draw bonds between them according to the functional group.

3. Add all of the other bits and pieces on.

4. Draw on all of the hydrogen atoms. Yes, you have to do this step. My Chem teacher told us that this guy from another class offered his brother $5 if he would draw on all of the hydrogen atoms for him. The brother looked at how many he had to draw and said, "Not worth it!"

Obviously, you need to draw all of the bonds on but I kind of ran out of room and couldn't be bothered rearranging stuff.

So that's pretty much all of the basic stuff on naming and drawing organic compounds. I've only really covered alkanes, but alkenes and alkynes aren't too different. The only thing is that you need to put the location of the double and triple bond just before the -ene or -yne suffix (e.g. but-2-ene). If you want me to clarify, just ask!

Radicals 木 水 手

Are you having trouble learning Chinese characters? If you are, I highly suggest that you learn some radicals.

What are radicals? you might ask. Radicals are the building blocks that make up a Chinese character. Pretty much all of them also exist as basic characters on their own (like 水 and 手). No complex Chinese character is totally unique- what looks like a complex character is really just made up of lots of basic characters. You also need to know radicals to be able to look up a Chinese character in the dictionary.

In this post I'm going to introduce just a few of the more common radicals and some of the characters in which you can find them.

木 = tree

It even looks like a tree. Yay.

Here are some characters that use this radical:

林 - woods
森 - forest (by the way, 森林 also means "forest")
杏 - apricot
松 - 松树 means "squirrel." By the way, 松 is pronounced "sōng" while the radical on the right of the character is pronounced gōng, which is kind of similar. Often what you find in Chinese characters is that one radical contributes to meaning and the other contributes to sound (though it is a rather vague clue).
树 - tree
枯 - withered

水， 氺, 氵 = water

The one on the right is the one you'll see most often. It looks like a few drops of water (to me, anyway). According to Wikipedia, this radical appears in some 1 595 characters!

Some characters:

游泳 - swimming (I put both characters together because they both contain the radical)
冰 - ice (by the way, the left hand radical means "ice" on its own. If you were to look this character up in the dictionary, you would look it up using the "ice" radical, NOT the "water" radical.)
洲 - continent
洋 - 大洋洲 means "Oceania."
渴 - thirsty. Not to be confused with 喝 which means "to drink."
浅 - shallow
深 - deep
池 - pond, pool
江 - river
河 - river (I think the difference between 江 and 河 is that one goes to the ocean while the other doesn't. Something like that anyway.)
汤 - soup

手，扌,龵 = hand

To be honest, I'd never realised that the one on the right was a variant of the "hand" radical...

捉 - catch
打 - hit
搓 - rub
扔 - throw aside
找 - look for something
指 - point out
拍 - hit, take a photo (obviously depends on context. Also with the "hit" meaning, I don't think it's really hitting as such. I'm pretty sure that 拍拍手 refers to those hand-clapping games that kids play, for example.)

I can't be bothered adding any more radicals for now. I'll endeavour to add 3 a day. We'll see if I can stick to that.

Basics of Organic Chemistry

I've decided to skip redox after all and talk about Organic Chemistry. Apart from redox being more annoying (well, actually drawing Organic Chemistry diagrams is a rather annoying task as well) I also have a validation test or something like that for Organic Chem next week.

Organic chemistry is the study of organic compounds. I'm not entirely sure what the definition of an organic compound is, but I do know that most of them are hydrocarbons (compounds containing mainly hydrogen and carbon, but some have halogens or other nonmetal elements like oxygen and nitrogen attached to them too). When you study organic chemistry, you're pretty much just dealing with hydrocarbons anyway.

Why hydrocarbons? you may ask. Well, carbon is a pretty special element simply because of the way it bonds. Yeah, it bonds using good ol' covalent bonds, but since it's a group 14 element, it can form 4 bonds. (See Covalent Bonding for more info on covalent bonding.) Being able to form 4 bonds is great- it means carbon can bond to up to 4 other atoms (including other carbon atoms) and it can form single, double or triple bonds (but not quadruple bonds otherwise all the electrons'd throw a fit from all being shoved in the same space together). Now, why carbon and not any other group 14 element? Why don't we have, say, hydrosilicons or hydrogermaniums or... hydrotins? Well, I've been told time and time again that carbon is special because it's not overly fussy about the atoms that it bonds with, and is also able to form long carbon chains and rings. I'm not 100% sure on this one, but I'm guessing that these two attributes must be unique to carbon or carbon does these things better, resulting in more hydrocarbons than hydro- anything else. In fact, there's a hell of a lot of hydrocarbons simply because of the way carbon bonds.

Now there's different types of hydrocarbons, grouped depending on how many bonds they have and whether the carbon atoms are bonded in chains or rings. I've even drawn a diagram with pretty colours to show you how they're categorised and what the groups (which I'm pretty sure are called "homologous series") are called. (These aren't all the homologous series, just the ones studied in Year 11.)

By the way, I'm pretty sure that the criteria that we use to categorise hydrocarbons (e.g. double bonds, triple bonds, presence of benzene etc.) are known as "functional groups." So "homologous series" are the group names and "functional groups" are the defining features of the groups.

As you can see from the diagram above, alkanes are carbon chains with single bonds only, alkenes are carbon chains with at least one double bond, and so on.

One thing that I forgot to add to my diagram is the special names for hydrocarbon chains and hydrocarbon rings. Hydrocarbons in chain formation are known as aliphatic hydrocarbons while hydrocarbons in ring formation are known as alicyclic hydrocarbons.

Right. Now on to drawing some basic hydrocarbons so you can see what they look like.

Meet ethane. It only has single bonds (a line is a shorthand way of writing a bond) and is in a chain. Therefore, it's an alkane. In the name "ethane," the "-ane" comes from "alkane" and the "eth-" indicates that there are 2 carbons.

Why don't they call it biane or diane? I don't know. Chemistry likes to be different, so in naming hydrocarbons there's a few special prefixes telling you how many carbons are in the main hydrocarbon chain. (I say "main" because, as we shall see later, some hydrocarbon chains and rings have branches.) You'll have to learn the special names for small numbers of carbon, but as the number of carbons increases, the names will settle back into normality because evidently the IUPAC's (International Union of Pure and Applied Chemistry) imagination only goes so far.

1: meth-
2: eth-
3: prop-
4: but-
5: pent-
6: hex-
7: hept-
8: oct-

By the way, I've always been interested as to what 11 is, so I googled it. It's undec-. 12 is dodec- and 13 is tridec-. And for you superstitious people who don't like me ending on 13, 14 is tetradec-. Wikipedia has the prefixes for 15, 20, 30, 40 and 50. It's like learning to count in a foreign language...

Now all alkanes have a few things in common. First of all, since they already have their hands (bonds?) full with hydrogen, they're not all too willing to react. They will undergo combustion reactions (just like every other organic compound that I know of), reacting with oxygen to produce carbon dioxide and water (which is usually seen in the form of steam due to the high heat in the highly exothermic combustion reaction), but apart from these they'll only undergo substitution reactions in which one of the hydrogens is substituted for another element. Substitution reactions can only take place if there's a catalyst present, like UV light. (Wait, does UV light count as a catalyst? I don't know.)

Oh wait, I just introduced another standard equation. Let's make it official.

Organic Compound + Oxygen gas -> Carbon Dioxide + Steam

Maybe I should also give an example for a substitution reaction just to make it clearer. How about our dear friend ethane with bromine water?

C2H6 + Br2 -> C2H5Br + HBr

As you can see, one of the hydrogens has swapped places with one of the bromines. If bromine is in excess there are different compounds that can be formed, but I don't know all too much about this.

Another similarity between alkanes is the general formula of alkanes. You see, each carbon has 2 hydrogen atoms bonded to it, while the carbon atoms at either end of the chain have one extra hydrogen each. Therefore, the number of hydrogens is double the number of carbons add 2. This can be summed up in a neat little general formula:

CnH2n+2

Let's meet another hydrocarbon- an alkene this time. Meet ethene- "eth-" for two carbons, "-ene" because it's an alkene.

As you can see, the double bond means that ethene can't contain as many hydrogens as ethane. We could also say that ethene is unsaturated because it doesn't have the maximum amount of hydrogens, while ethane is saturated because it can't hold any more hydrogens.

Alkenes are more reactive than alkanes due to the double bond. The double bond can break to bond with new elements in addition reactions. For example, if ethene was to react with bromine water, this reaction would occur:

C2H4 + Br2 -> C2H4Br2

Easy, no?

Like alkanes, alkenes also undergo combustion reactions. Also like alkanes, alkenes have a special general formula, but theirs is different from that of alkanes. The general formula of alkenes is as follows:

CnH2n

You don't have to learn about alkynes in year 11, but it should be pretty obvious what they'd look like. Ethyne would be like ethene but with an extra bond in the middle and two less hydrogens to compensate. Alkynes also undergo addition and combustion reactions. The general formula of alkynes is CnH2n-2.

Cycloalkanes are basically alkanes arranged in rings. Here's cyclopropane (cyclo- because it's cyclic, prop- because there's three carbons and -ane because it's an alkane):

Cycloalkanes behave in pretty much the same way as regular alkanes, but they have a different general formula. The general formula of cycloalkanes is the same as the general formula of alkenes, that being CnH2n.

Cycloalkenes are cycloalkanes with a double bond and two fewer hydrogens to compensate. Again, they behave like cycloalkenes, but have the same general formula of alkynes, that being CnH2n-2.

Last but not least, we have the aromatic compounds. That requires talking about benzene. Say hi to a simplified version of benzene!

Benzene has the formula C6H6 and it is a very special compound because its bonds aren't a regular length and it has a whole bunch of delocalised electrons in the middle, represented by that circle in the middle. The bonds of benzene are between the length of a single and a double bond. Each carbon atom has 3 bonds: one between the carbon and an adjacent hydrogen atom and the other two between the carbon atom and adjacent carbon atoms. The remaining electron makes up the sea of delocalised electrons in the middle. Unlike graphite, however, which also has delocalised electrons, benzene doesn't conduct electricity because all of the delocalised electrons are still somewhat localised to one molecule, whereas in graphite, the delocalised electrons are free to travel throughout the whole network. (For more info on graphite, see my post on covalent bonding.)

Basically, an aromatic compound is a compound that contains benzene. Since benzene has those weird bonds which are single bonds but are shorter than normal single bond lengths, benzene is only as reactive as an alkane- that is, it only undergoes catalysed substitution reactions or combustion reactions, but not addition reactions.

So there you have it- the basics of Organic Chemistry. Next up is drawing and naming hydrocarbons!

Chinese views on education as seen in 女生日记, part 2

I didn't get to finish saying everything I wanted to say in my first post, so here's a second post.

梅小雅 (Mei Xiaoya) and Family

Mei Xiaoya's mum does something quite strange at the beginning of the novel which is revealed to be her plan to get Xiaoya into a good middle school. I think that her idea is that in a good primary school, such as the one Dongyang and her friends attend, the increased competition would compromise Xiaoya's chances of getting into a good middle school, whereas if Xiaoya goes to a normal school that still has had students go to a good middle school, then her chances might be increased. Mei Xiaoya isn't happy with the decision because she liked her friends at her old school, but she can't go against her mother's wishes.

When asked by Dongyang as to why Xiaoya's mum would force her to change schools when she clearly doesn't want to, Xiaoya replies, “我不怪我的妈妈。 她过得很苦，我是她惟一的希望，她说这一辈子的愿望就是要让我读大学，做一个有出息的人。” (I don't blame my mum. She's had a bitter time, and I'm her only hope. She says that her lifetime dream is for me to go to university and to have a future.) Here, at least, Xiaoya's mum's reasons for Xiaoya to do well are clear. Xiaoya's mum's desires are born out of poverty and of the misery of her own life and the innate parental desire for their children not to have to grow up the same way. However, she is not quite so pushy as Zhao Xiaowei's mum, as evidenced by the fact that Xiaoya's mum at least allows Xiaoya to help out in the family business. (I'm not sure what Zhao Xiaowei's mum's motives are, but they're probably quite different. It seems to me that Zhao Xiaowei's parents have a reasonable amount of money. In the chapter about the Teachers' Day gifts, Dongyang writes about what Xiaowei's parents work as, but I still can't work out what they are, not even with a dictionary. Something to do with being a Deputy Secretary and a Deputy Commissioner of some bureau. I don't know.)

舒老师 (Shu Laoshi/ Mr Shu)

Shu Laoshi, who the students initially loved for his good looks, eventually comes to be loved for other reasons. In the chapter “没有分数的试卷” (Exam papers with no [numerical] marks), Shu Laoshi gives out letter grades as opposed to percentages. His justification is that he occasionally hears stories about students being punished by their parents for not getting 100%. He believes that in using more vague grades, “压力不那么大，情绪也就不那么紧张了” (the pressure won't be so great, and you won't feel so nervous). He then goes on with what I perceive to be his trump card: “再说我们学习并不仅仅为了考试，分数不能说明一切。” (Besides, our study isn't only for exams. The marks don't tell you everything.) Not long after, he says, “总之一句话，考试不是目的，如果我是教育部长，马上取消考试。” (Overall what I'm saying is that exams aren't "eyes." If I was the Minister of Education, I would immediately get rid of exams.") This is greeted with much enthusiasm from the students, who say, “舒老师万岁！” (Long live Shu Laoshi!)

The parents aren't so thrilled though. In a later chapter, “所有人的难题” (Everyone's Difficult Question), 南柯梦 (Nan Kemeng) tells Dongyang that she's concerned that Shu Laoshi might lose his job, or at least won't be allowed to teach them any more. You see, many parents of students in the class went and saw the principal with their concerns that Shu Laoshi isn't using number grades and is assigning very little homework. They're concerned that their children will do badly in the all-important primary school graduation exam. Nan Kemeng's own grandmother, who used to be a school principal, is likewise concerned that Nan Kemeng isn't getting as much homework as her older cousin did when she was in Nan Kemeng's year.

The students are worried and plan to see the principal about it. Interestingly, 郝佳 (Hao Jia), the class leader, won't go and see the principal herself despite her classmates' assertions that, as the class leader, she should go and see the principal. She says, “如果老师让我去，我就去” (if the teacher asks me to go, I'll go), which epitomises the reason why student councils and whatnot don't mean very much to me. Back on topic, some students (吴缅 (Wu Mian) and 鲁肥肥 (Lu Feifei, which I'm guessing is a nickname as "fei" means "fat") eventually do decide to go and see the principal, who offers to have a meeting with their class at some point. I don't know what the outcome of the meeting is because I haven't read enough of the book yet.

At this point Dongyang's family are shown to be on Shu Laoshi's side. When Dongyang talks to her parents about the day's events, her dad says, “如果我有机会见到[舒老师]，我要对他说声 ‘谢谢’！” (If I ever get the opportunity to see [Shu Laoshi], I want to say 'thank you'!) After Dongyang talks about the other parents' viewpoints, her mum says, “我认为重要的是我女儿对数学有兴趣了。” (I think that it's important that my daughter has an interest in maths.) They then go on to talk about their comparatively more relaxed childhoods, with little to no homework and an earlier school finish time. Dongyang's dad said that he used to play on the beach while her mum said that she used to go to a special centre for children and teenagers where she could join a choir and do drama. It didn't stop Dongyang's dad from becoming an architect and Dongyang's mum from becoming an MC. In fact, perhaps their childhood activities helped them with their current careers. As Dongyang writes about her mum and her job, “跟她小时候的这些活动经历有没有关系呢？” (Is there a relationship with the activities she experienced as a child?)

So there you have it- an introduction to different viewpoints on education in China, courtesy of 女生日记。 I hope you enjoyed it!

Chinese views on education as seen in 女生日记

A couple of years back, my mum went to Singapore and bought me some Chinese books. I couldn't read them at the time. Recently, even though I still can't read every word, I decided to try and read one of the books, skipping over the words that I don't know. The book is 女生日记 (Nüsheng Riji- A Schoolgirl's Diary) by 杨红缨 (Yang Hongying). I think it's also been made into a movie and a TV series, but I haven't seen either of them. Once I think I found the TV series online, but unfortunately it was on a Chinese online video site that only works if you're in China (I can't quite remember what the website was called- I think it was called youku but I could be completely wrong). I've only read about half of it, but I want to share with you what I've found so far.


Being the diary of a schoolgirl, a fair few of the chapters are about the stuff that every schoolgirl around the world goes through. In the first chapter, all of the girls are excited because being in the graduating class (in China, the primary school graduation class is Year 6- 11-12-year-olds) means that they get to have the hot maths teacher 舒老师 (Shu Laoshi or Mr Shu).There's some other chapter in there about picking which desk to sit at, and another chapter about hair that I couldn't understand much of. And, of course, there's a couple of chapters about puberty, including one aptly titled “女孩子的秘密” (Nühaizi de mimi- Girls' Secrets). I'm sure you can guess what that one's about. That's the chapter where I learned useful words like 月经 (Yuèjīng- the proper way to say "menstruation," lit. "monthly event/occurrence") and 那个 (nàge- the informal way to say "period," lit. "that thing," which I think describes periods pretty well).

Apart from that, though, there are a whole bunch of characters dealing with some very realistic issues, mainly related to family and school. 梅小雅 (Mei Xiaoya) lives only with her mum after her parents' divorce. Mei Xiaoya and her mum are relatively poor but do what they can to get by. Eventually they have the opportunity to start their own business. Another character, 莫欣儿 (Mo Xin'er) initially appears to be a happy schoolgirl, but soon that's revealed to only be a façade. Then there's Shu Laoshi, who endeavours to inspire a love of maths in his students but is confronted by an army of Chinese parents who criticise him for not giving number grades and assigning what they deem to be not enough homework.

Among all of the issues discussed in this book, I would have to say that the school issues grabbed my attention the most, possibly due to my Western background. (I'm half white, half Asian, but I've lived all my life in a Western country.) If 女生日记 is anything to go by, even though there are quite a few Tiger Mums in China, there are a few relaxed parents too. I'm going to talk about some of the characters and their key lines here with regards to their views on education.

冉冬阳 (Ran Dongyang) and Family

(I've read 154 pages without knowing what her last name is... I only looked it up just then! As I said, I'm skipping over words I don't know, only looking them up if they occur lots of times.)

Dongyang's family appears to be of the relaxed type- or at least, throughout the course of the first 154 pages of this book, they're quite relaxed. I have a feeling that Dongyang's mum wasn't quite so relaxed in the past, because when she tells Dongyang that she was 18th in her class (out of 48), the first thing Dongyang asks is “你为什么没有骂我？” (Why didn't you scold me?). Dongyang's mum's explanation is representative of her changed attitude. After talking about Dongyang's exam results (100% for maths, 93% for Chinese- to be honest, I'm a bit creeped out by the fact that 17 people managed to top that), she asks “分数不能说明一切，我认为你已经努力了，干吗还要骂你？” (The marks don't tell all, I think that you already work hard, do I still have to scold you?)

Happiness seems to be of most importance to the Ran family- more so than intelligence. In the chapter “烛光晚饭” (Candlelight Dinner), Dongyang asks her father what he wants her to be, prompting the following conversation. (Dialogue does not appear like this in a Chinese novel- it appears very much like in an English novel- but I've used drama/play format for simplicity.)

冬阳： 我。。。 我在想我长大以后，你希望我做一个什么样的羊？ (I... I was thinking that when I grow up, what kind of person do you want me to be?)
爸爸： 做一个快活的人。 (A happy person.)
冬阳： 做一个快活的人？ 你对我的要求是不是太低了？ (A happy person? You have such a low request for me?)
爸爸： 怎么，你觉得做一个快活的人不好吗？ (What, you think that being a happy person isn't good?)
冬阳： 我知道我是一个平凡的女孩，不聪明，不漂亮，也没有什么特别的才华，所以你对我不抱很高的期望。 (I know that I'm an ordinary girl, not clever, not beautiful, and I also don't have any special traits, so you can't hold me to any high wishes.)
爸爸： 你错了，冬阳。 对一个女孩来说，聪明和漂亮并不是最重要的，温柔善良才是女孩子最宝贵的品质。 不聪明，不漂亮的女孩，会因为温柔和善良而变得可爱起来。 冬阳，你就是一个非常可爱的女孩，爸爸爱你，所以希望你快乐，永远快乐，这就是我对你的最高期望。(You're wrong, Dongyang. I say that for girls, intelligence and beauty aren't the most important, gentleness and kindness are the most important qualities of a girl. Girls who aren't beautiful or clever can become lovely because of their gentleness and kindness. Dongyang, you are an extremely lovely girl, Daddy loves you, so I wish that you can be happy, forever happy. This is my highest wish for you.)

Sidenote: 可爱 often means "cute," but according to Google Translate it can also mean "lovely" or "amiable."

Dongyang then goes on to write about how her dad says that being a happy person isn't easy, which Dongyang doesn't completely understand. Her dad explains that she'll slowly begin to understand as she gets older.

I wonder whether Dongyang's inability to understand the idea that happiness is of utmost importance comes from her upbringing in Chinese society. Sometimes I wonder whether I'm being racist or simply too diagnostic by thinking that in the first place. My thoughts on this come from when I learned the Chinese word 理想 (ideals/ambitions). My Chinese tutor told me that Chinese kids are always encouraged to have very big ambitions. She said that good ambitions would include becoming a doctor or lawyer, while you would be laughed at if you said that you wanted to be a farmer. (I must admit that the whole idea of respectable jobs isn't just limited to China- I remember reading something along those lines on a blog of an American woman.) It seemed to me that in Dongyang's mind, simply being happy wouldn't have seemed like a very high-reaching ambition but I think the slow journey to understanding takes place within the course of the novel as well. Actually, I quite like the way Dongyang changes and develops throughout 女生日记 (which I think is essentially a novel about growing up). I could go on about her but I won't. Not at this point, anyway.

赵晓薇 (Zhao Xiaowei) and Family

Argh, Zhao Xiaowei's mum... now she's your Tiger Mum. Zhao Xiaowei and Ran Dongyang started off in the same class, but soon Xiaowei's mum arranged for her to move out of that class because she didn't like Xiaowei's teacher. You see, 罗老师 (Luo Laoshi) had just graduated from Teachers' College and had no teaching experience, and Zhao Xiaowei's mum didn't like the idea of that at all.

Zhao Xiaowei's mum is intent on getting Xiaowei into a good middle school and will do whatever it takes, including coming pretty damn close to bribing the teacher with a really expensive gift on Teachers' Day. The Zhao family bought Xiaowei's teacher an expensive watch costing over 1000 yuan, while the Ran family was happy for Dongyang to just give her teacher a card. Xiaowei insists that you can't get away with just giving a teacher a card when you're in the graduating class, which confused Dongyang greatly. Xiaowei's explanation is that “能不能考重点中学， 全看老师的了。” (Whether or not you can go to a good middle school depends on the teacher.) Dongyang says that she thought that it was based on exam marks, to which Xiaowei says something that I don't understand, but it seems important, so I'll post it here so that any Chinese speakers can help me on this one.

“你真是榆木脑瓜不开窍。” 赵晓威说话的样子跟大人一样， “每个班不是有一个区三好学生的名额吗？ 把这个名额争到了，毕业成绩上加1分呢。”

I understand the bit between the spoken bits, where it says that Zhao Xiaowei is speaking like an adult. But I don't really understand what Zhao Xiaowei's saying, particularly the first bit because I think that's a Chinese expression. For the second part, I can see that there's something about fighting for being in the top 3 and having an extra point added on to the final graduation grade, but I'm not quite sure.

Then Xiaowei says something else. Again, I don't understand the first bit, but I understand the second bit.

“还不是老师的一句话，他们说你行你就行，说你不行你就不行。”

I think the first bit is something along the lines of "but doesn't it all come down to what the teacher says."  The next bit is "If they say you can, then you can; if they say you can't, then you can't."

The conversation leaves Dongyang feeling sour and cold towards Xiaowei. She writes in her diary that “现在，我更不喜欢她了，我在她身上已看不到一点天真的东西，她不像一个孩子，而像一个老练的小大人。” (Now, I dislike her even more. When I'm with her I can't see a bit of innocence. She's not like a child, but like someone who's practised for a while at being a little adult.)

Now the real fireworks fly when Tiger Mum Mrs Zhao meets up with How-Can-I-Scold-My-Diligent-Daughter Mrs Ran in the chapter titled “情商和智商” (EQ and IQ). Now this is the mother of all conversations/arguments. I could say that conversation represents the conflict between Western and traditional Asian views on education, but maybe that's my racism coming through again. Or is it impossible for me to be racist, given that I'm half Asian and half white? Whatever. This is probably a bit superfluous, but here's the meaty part of the conversation (which is like 90% of the chapter, but whatever).

赵女士： 我今天来是想你取经来了。 (I've come today because I want you to learn something.)
冉女士： 取经？ 取什么经？ (Learn? Learn what?)
赵女士： 是这样的。 你家冬阳和我家晓薇不是都读毕业班了吗？ 你们对冬阳采取了什么有效的措施没有？ (It's like this. Aren't your Dongyang and my Xiaowei both in the graduating year? Haven't you taken any effective strategies with Dongyang?)
冉女士： 没有，还跟以前一样。 还必要采取措施吗？ (No, just doing the same as before. Must we adopt strategies?)
赵女士： 还必要，太有必要了，现在是多么关键的时刻啊！老同学， 你是不是在向我保密？ 我听晓薇说，教师节你们都没给老师送礼，我就在想，是不是你们家冬阳上重点有把握了？ (You must, you really must, now is the crucial time! My old classmate, don't you trust me? I heard Xiaowei say that on Teachers' Day you didn't buy the teacher a present. I'm thinking, is Dongyang guaranteed a place in a good middle school?)
冉冬阳： 阿姨，我们老师不收礼物。 (Auntie, our teacher doesn't accept presents. [Note from me: In Asian cultures, it's polite to call people our parents' age "auntie" and "uncle." I call my mum's friends "auntie" and "uncle" as well.])
赵女士： 这年月已经没有不收礼物的老师了。 (By this time there wouldn't be any teachers not accepting gifts.)
冉冬阳： 我的老师真的不收礼物，你不信，去问问。 (My teacher really doesn't accept gifts. If you don't believe me, go and ask.)
冉女士： 冬阳！ (Dongyang!)
赵女士： 李妹，你给你女儿请家教，上补习班没有？ (Li Mei, do you give your daughter tuition or extra classes? [Note from me: Li Mei is probably not Dongyang's mum's name. I'm guessing that Li is her maiden name. "Mei" means "little sister." I could be wrong, though- perhaps Limei is her name.])
冉女士： 没有。 (No, I haven't.)
赵女士： 做其他书上的习题，作文没有？ (Don't you do extra questions or write extra compositions?)
冉冬阳： 也没有。 (Also no.)
赵女士： 那你怎么安排你在家的时间？ (Then how do you organise your time when you're at home?)
冉冬阳： 做完作业，就做自己想做的事情。 (I do my homework, then I do things that I want to do.)
赵女士： 李妹，没想到你女儿倒是蛮有个性的。 ([I couldn't quite work out what this sentence meant on my own, so I had to use Google Translate to get the gist of it. Google Translate actually gave me something intelligible this time.] Li Mei, I didn't know that your daughter had quite the personality.)
赵晓薇： 冉冬阳， 你明天干什么？ (Ran Dongyang, what are you going to do tomorrow?)
冉冬阳： 梅小雅你还记得吧？ 现在她妈妈开了家小店，她妈妈一直在生病，所以我明天一早要陪小雅到三合堡小食品批发市场去进货。 (Do you still remember Mei Xiaoya? Her mum's opened a family shop, but she's recently fallen ill, so tomorrow I'm going to accompany Mei Xiaoya to the Sanhebao Wholesale Snack Market to stock the shop.)
赵女士： 什么，进货？ (What, stock the shop?)
冉冬阳： 对，去进货。 (Yes, stock the shop.)
赵女士： 就你们两个小姑娘？ (You two young ladies?)
（冬阳点点头。 Dongyang nods her head.)
赵女士： 我说李妹，你怎么能让你女儿这么复杂的地方？而且，小小年纪，进什么货呀？ (I say, Li Mei, how would you allow your daughter to go to such a complicated place? Furthermore, at such a young age， how would they stock the shop?)
冉女士： 现在的孩子生活得太幸福了，让他们早一点体验生活的艰辛，我觉得没什么不好。 (Today the lives of children have become really fortunate, allowing them to experience the hardships of life a little earlier. I do not think that that's a bad thing.)
赵女士： 你有没有搞错哇，李美？ 你女儿正在读毕业班哪！(Haven't you done something wrong, Li Mei? Your daughter is currently in the graduating class!)
冉女士： 建华，你有没有这样的体会，现在的孩子普遍IQ高，EQ低？ (Jianhua, did you know that currently the general IQ of children is high while their EQ is low?)
赵晓薇： 李妹阿姨，什么是IQ，什么是EQ？ (Auntie Li Mei, what's IQ and what's EQ?)
冉女士： IQ是智商，EQ是情商。 现在的孩子都是独生子女， 大多养成了以自我为中心的习惯， 不知道替别人着想，不体谅别人的难处。。。(IQ is Intelligence Quotient, EQ is Emotional Quotient. [Note from me: At this point, Dongyang writes that she still doesn't understand what EQ is, but she understands what IQ is.] Today's children are all single children, and many develop self-centred habits, not knowing how to empathise or understand other people's difficulties...)
赵女士： 李妹，你到底要说什么？ 你别忘了，我不是你热线节目里的听众，我是你的老同学。 (Li Mei, what are you saying? Don't forget, I'm not your audience, I'm your old classmate. [Note from me: Dongyang's mum is an MC.])
冉女士： 对不起。 我是想说，我很庆幸我女儿有梅小雅这么一个朋友，在她们的友情中，使我女儿得到了因为帮助别人而带给她的快乐。 (Sorry. I want to say that I'm very happy that my daughter has a friend like Mei Xiaoya. In their friendship, my daughter will gain that happiness that comes from helping other people. [Note from me: I'm not 100% sure that this is what Dongyang's mum is saying.])
赵女士： 李妹，我还是不明白你在说什么？ (Li Mei, I still don't understand what you're saying.)
冉女士： 简单说吧， 如果在智商和情商之间作选择，我愿意我女儿做一个高情商的人。 (Simply put, if I had to choose between IQ and EQ, I would want my daughter to be a person with a high EQ.)

As Zhao Xiaowei and her mum prepare to leave, Xiaowei then whispers something to Dongyang which I think is quite important. She says, “冬阳，我好羡慕你！” (Dongyang, I really envy you!) I think this one line illustrates a big change in Xiaowei from blindly following her mum's beliefs to believing that there is a better way. Of course, Xiaowei could have wanted the EQ path for herself previously, but was too afraid/ wasn't willing to show it.

That Tiger Mum is such a b****. I mean, she met up with her old classmate who she hadn't seen in 3 years solely to criticise the way she's handling her daughter's education, and then good ol' Tiger Mum ups and leaves when she realises that she can't turn everyone else into Tiger Mums. Gah.

(To be continued)

Acids and Bases part 2

For part one, click here.

In Part 1, I talked about basic properties of acids and bases, the Arrhenius and Bronsted-Lowry theories, strong and weak acids and bases and some standard reactions. Today I'm going to finish off the standard reactions, and then go off onto some slightly new stuff. (I say "slightly new" because nothing you learn at this stage is really completely new but has its roots in something you already know. Remember that when you're learning "new" stuff, okay?)

Okay, on to some new standard reactions-  amphoteric metal/metal oxide/metal hydroxide reactions with bases. I hate these reactions. I know that expressing my hatred for these reactions isn't going to help you learn them, but whatever. Adding to my hatred for amphoteric metal reactions is that I can't explain them to save my life, which is also why I can't remember them. It doesn't help that complex ions are annoying either (in my humble opinion anyway).

First up is the good ol' amphoteric metal + base reaction:

Amphoteric metal + base -> complex ion + hydrogen gas

2Al + 2NaOH + 6H₂O à 2NaAl(OH)₄ + 3H₂

Then there's the amphoteric metal oxide and amphoteric metal hydroxide with base reactions:

Amphoteric metal oxide + base -> complex ion

Al₂O₃ + 2NaOH + 3H₂O à 2NaAl(OH)₄

Amphoteric metal hydroxide + base -> complex ion

Zn(OH)₂ + 2NaOH à Na₂Zn(OH)₄

Please note that the amphoteric metal and amphoteric metal oxide reactions occur with water as a reactant.

I can't really explain what a complex ion is (okay, well I can tell you my inference that a complex ion has both a metal and a non-metal component, but you probably already inferred that), but I can give a few examples from my revision book:

Tetrahydroxoaluminate (aluminate): Al(OH)₄^-

Tetrahydroxozincate (zincate): Zn(OH)₄^2-

Tetrahydroxochromate (chromate): Cr(OH)₄^-

Don't get too scared by those super-long names, by the way. Just remember, "tetra" means 4 and "hydroxo" is a reference to the hydroxide ion. Anyway, you don't really need to know the names of these ions.

The charge on the ion is just the positive charge on the metal part subtract 4 (since each hydroxide ion contributes a -1 charge and there are four hydroxide ions in a tetrahydroxo- complex ion).

Since I don't really understand amphoteric metal equations, the way I memorise these is just by thinking about what's similar and what's different between the three equations. Remembering which equation corresponds to which difference is the problem though...

The main similarity is that all equations produce complex ions. There are a couple more obvious differences though.

Differences:

• Only the amphoteric metal reaction produces hydrogen gas. Maybe this is due to the lack of oxygen atoms attached to the original amphoteric metal.
• Only the amphoteric metal hydroxide reaction doesn't involve water. I'm guessing that this is due to the fact that a hydroxide already includes hydrogen atoms so that a reaction with water isn't required.

Now that I've written that, it seems to make slightly more sense to me...

Now onto the slightly new stuff. First I'm going to talk about monoprotic and polyprotic acids. Monoprotic acids only have one hydrogen atom per molecule, while polyprotic acids have multiple hydrogen atoms per molecule and therefore can ionise multiple times. Remember, mono- means one, and poly- means multiple. You can also call acids with two hydrogen atoms per molecule "diprotic" acids, and I'm assuming that you can call those with three hydrogen atoms "triprotic" acids.

I'm going to provide an example on how polyprotic acids undergo successive ionisation. The example that I'm going to provide here is a strong diprotic acid, sulfuric acid.

H₂SO₄ + H₂O -> H₃O⁺ + HSO₄^-

HSO4^- + H₂O <--> H₃O⁺ + SO₄^2-

In the first reaction, sulfuric acid completely ionises to form the hydrogen ion (which doesn't exist very long in water and quickly forms the hydronium ion) as well as the hydrogen sulfate ion. The hydrogen sulfate ion then reacts to produce the hydrogen-then-hydronium ion, as well as the sulfate ion. Since hydrogen sulfate is a weak acid, it only partially ionises in water. Some hydrogen sulfate will stay as hydrogen sulfate. The final solution (by this I mean what you end up with as a result of these reactions, not the Nazi Party's Final Solution of course- sorry for the really lame not-very-funny joke) will therefore have no sulfuric acid, lots of hydronium ions, quite a few hydrogen sulfate ions and a small amount of sulfate ions.

All this talk of hydronium ions reminds me that I need to tell y'all about pH. pH, which runs on a scale between 1 (or is it 0?) and 14, is a measure of how acidic or basic a solution is. Acids have a low pH while bases have a high pH. Neutral substances have a pH of 7. You can measure the pH of a substance by using an indicator such as litmus paper or universal indicator.

Mathematically, though, what is pH? Well, pH runs on a logarithmic scale, which is why I wrote about logs before I wrote this post, in a post aptly titled "Logarithms," though I must say I didn't explain logs all too well there. Here's the equation:

pH = -log [H+]

[H+] is hydrogen ion concentration (in moles/litre).

Don't worry, mathophobes, it's easy enough to plug this equation into a calculator to get the pH from the hydrogen ion concentration. (You don't even have to remember the equation because it's in your data sheet.) The hard part is getting the hydrogen ion concentration in the first place.

With a strong acid, it's easy. (Well, if it doesn't require more effort than I think it requires, then it's easy.) Since a strong acid completely ionises in water, the number of moles of hydrogen in the strong acid is the number of moles of hydrogen ions in the resulting solution. Weak acids are a bit different, though, because you have to know what percentage of the acid actually ionises. I've never actually gotten a weak acid question, but I assume that what you do is you work out the number of moles as normal, but then you multiply this by the percentage required.

With bases, where you're normally given something random like hydroxide ions to work with, it's slightly harder. What we have to think about here is the water constant, which is 1 * 10^(-14) (which is really just 10^(-14)). The product of the hydrogen ion and hydroxide ion concentrations is equal to this water constant. (You don't have to remember this number either because it's also on your data sheet.) We now have a nifty little formula for you to rearrange and use and abuse at your will in order to work out hydrogen ion concentrations.

[H+][OH-] = 1 * 10^(-14)

As long as you can figure out either the hydrogen ion or hydroxide ion concentrations, you can work out the concentration of the other kind of ion. You can take the hydrogen ion concentration to work out the pH.

Maths-savvy people would know that you can rearrange the pH equation to get another useful equation (full working is provided to make up for my terrible explanation on logs in the other post):

pH = -log [H+]
-pH = log [H+]
10^(-pH) = [H+]

Now you can whack in the pH to find the hydrogen ion concentration! Yay!

All this stuff about pH gives us one more way in which we can differentiate acids and bases. Acids have a low pH while bases have a high pH. Therefore, most indicators will show different colours depending on whether it's an acid or a base that you're looking at. (However, some indicators have a narrow range and are better used for distinguishing weak acids from strong acids or something along those lines, so be careful.)

Last thing I need to talk about is properties and reactions of non-metal and metal oxides including their reaction with water. Now, this is a topic that I'm shaky with and put a big asterisk (my symbol for "need to revise") next to. One thing I can tell you, though, is that most metal oxides are basic, just like metal hydroxides, which is why they neutralise acids (see Acids and Bases part 1). Most non-metal oxides are the opposite- they're acidic. (Mind you, this is a general rule only- there are amphoteric metal oxides and all that jazz.) Now, as for their reactions with water... I'll have to look it up in my textbook.

Acidic non-metal oxides with water- The oxygen from the water joins with the non-metal oxide to make an ion while the hydrogen from the water completes the package by turning that ion into an acid. Here's some examples:

CO₂ + H₂O -> H₂CO₃

SO₂ + H₂O -> H₂SO₃

_{Basic metal oxides with water- If the metal oxide is soluble, it will react to form hydroxide ions. The presence of all of these hydroxide ions means that the resulting solution is basic.}

_{Aaaand that's pretty much it for acids and bases. Next up will be either redox or organic chemistry- I'm thinking probably organic chem because I hate redox and want to give myself some more breathing room before I have to deal with it. If I'm in a really good mood tomorrow (or whenever I write my next post), though, I might do redox. We'll see.}

Logarithms

I'm baaaack! But this time I'm not talking about Chem: I'm here to talk about maths. About logs, to be exact. Mathematical logs. I'll never know why maths and chemistry like using the names of other objects to name stuff (I'm looking at you, 6.022 x 10^23, that number that chemistry named "the mole"), but at least in this case "log" is an abbreviation of something. Anyway, this is rather off topic.

I'm sure in your mathematical career you've encountered indices or exponentials. You know, those numbers to the power of something. Square numbers. Cubic numbers. Quartics. And so on. Well, logarithms are just the reverse of indices. Just like how multiplication and division are opposite processes.

Now, in exponentials, the big number at the bottom is called the base and I'm pretty sure the little number in the top right is the power. So in 2^3, the 2 is the base and the 3 is the power. Now, you see, logarithms also have different bases, as indicated in a little subscript next to the word "log"...

log_{2 = base 2 log}

log_{3 = base 3 log}

_{and so on. The most common base is base 10, so if you see "log" without a subscript, it's base 10 that's being referred to.}

_{Now, as I said before, logarithms are the opposite of exponentials. In exponentials, you have (base)^(power) = answer, but what happens if you have the base and the answer, but not the power? Well, this is where logs come in.}

Let's start simple. 2^x = 8. Now, log_{2 8 = x. Do you see what I did there? I put the base as a subscript next to the word "log" and then the answer. (I'm sure there's another term for this which is less vague than "answer," but I don't know what it is.) x = 3 because 2^3 = 8.}

_{But wait, you might ask. What happens if you get given some crazy numbers so you can't work out what x is in your head? Well, this is where log laws come in.}

You see, logs are the opposite of indices, so log laws are the opposite of index laws. If you multiply two exponentials together, you add the indices together. Conversely, if you add two logs together, you multiply the number next to the word "log" (not the subscript, I mean, the other number. I really need to know what this number's called...). If you divide an exponential by another, you subtract the indices. Conversely, if you subtract two logs, you divide the indices. There's explanations for these but I don't really want to put them up until I know what that damn other number is called, because I'm probably already confusing you enough as it is.

There's also another important log law to learn. If that-number-which-I-don't-have-a-name-for is an exponential (e.g. 2^3 or 3^5 or whatever), then you can rearrange it like this:

log_{2 (2^3) = 3} log_2 2

_{Basically I've just taken the power down to the front.}

_{Two more things that you need to know: if the base is equal to that number, then the answer's 1. That's because when you raise any base to the power of 1, the result is the same as the base. Also, if that number is 1, then the answer's 0, because anything to the power of 0 is 1.}

_{Okay. That was a really confusing explanation, mainly because I don't have a name for that number, and I really need a name that's less vague than "answer." One day I'll clean up this post. One day...}

Acids and Bases Part 1

You know how I said that there were only really 3 topics to cover for the second semester for Year 11 Chem? Well, there are, but within each topic there's quite a bit to cover. I'll see how much I can be bothered to do today, and if I can't be bothered doing every single dot point for acids and bases today, I'll do the rest tomorrow.

Okay, acids and bases. Where to begin? Well, defining what acids and bases are would probably be a good place to start.

First up, let's look at some of the basic properties of acids and bases:

Acids

• taste sour, like the citric acid in lemons. I don't recommend testing this by tasting 10M hydrochloric acid, however.
• are corrosive
• neutralise bases
• tend to conduct electricity well

Bases

• taste bitter
• are corrosive
• neutralise acids
• tend to conduct electricity well

But wait, you might say. Acids and bases share so many common properties! They're corrosive, they tend to conduct electricity well, and they neutralise each other! How do you tell them apart?

Well, there are differences at the chemical level. In the past, people have tried to form theories about it. Two of the main ones are the Arrhenius and Bronsted-Lowry theories. (The "o" in Bronsted actually has one of those lines through it, just like in I think Norwegian and Danish and a couple of other languages, but I can't be bothered putting in the effort to find out how to type it.)

Arrhenius' Theory- Acids release H+ ions in water and bases release OH- ions in water. It's a nice and simple theory which explains some properties of acids and bases like pH and neutralisation reactions, but it doesn't explain everything. It doesn't explain why not all bases have OH- ions, and it doesn't account for the fact that the H+ ion actually doesn't last that long in water before it becomes the hydronium ion (H3O+), but it was a pretty useful theory at the time.

Bronsted-Lowry Theory- Acids donate protons while bases accept them. This is based on the idea that a hydrogen ion is actually just a proton (most hydrogen atoms have no neutrons, and H+ ions are hydrogen atoms with one less electron, and since hydrogen only has one electron anyway, H+ ions effectively have no electrons). This is better than the Arrhenius Theory as it accounts for bases which don't have OH- ions, as well as substances that can act as bases AND acids (amphoteric substances- more on them later) but it's still not perfect and that's why some other theory called the Lewis Theory about electron pairs and whatnot was invented, but I don't know enough about the Lewis Theory to be able to teach you.

One more thing about the Bronsted-Lowry theory- the reactants are the acid and base, while the products are the acid with one less proton (or one more H, if you prefer) and the base with one more proton. There are special names for the products: the acid with one less proton is a conjugate base while the base with one more proton is a conjugate acid. Basically the conjugate acid and conjugate base act as the acid and base in the reverse reaction. Well, that's my understanding anyway.

One more way to tell acids and bases apart is through the use of indicators, like Universal Indicator and litmus paper (as well as certain vegetables if I remember correctly). These things change colour when placed into a solution of an acid or a base. Litmus turns red when put into an acid and blue when put into a base. Universal indicator does the same, but it also turns green if the solution is neutral.

Strong and weak acids is up next. Strong and weak acids basically follow the same rules as strong and weak electrolytes, i.e. strong acids completely dissociate or ionise in water while weak acids only partially dissociate in water. Unfortunately I think you more or less just have to remember which acids are strong and which are weak (yeah I hate memorising stuff too). Same goes with the bases. It's not too memory-intensive, though: the hardest part is memorising the strong acids.

As far as I know there are only six strong acids: nitric acid (HNO3), sulfuric acid (H2SO4), hydrochloric acid (HCl), hydrobromic acid (HBr), hydroiodic acid (HI) and perchloric acid (HClO4). All other acids are weak acids.

I think all metal hydroxides are strong bases. All other bases are weak bases.

The last thing I'm going to tell you about today is a few more standard equations to add to your collection.

Acid + Carbonate/Hydrogencarbonate -> Salt + Carbon Dioxide + Water

This is pretty much the same thing as I said in Reactions and Equations, part deux. The only thing now is that I've added hydrogencarbonates/bicarbonates into the mix. Carbonates and hydrogen carbonates react in the same way with acids which makes it easy to remember.

Acid + Metal -> Salt + Hydrogen Gas

A bit more deja vu, isn't it? This is another reaction that I mentioned in Reactions and Equations, part deux, so if you're confused, go read that post, or go Google it and find someone who actually knows how to explain stuff.

Acid + Metal Oxide/ Metal Hydroxide -> Salt + Water

Simple. The metal ion reacts with the anion in the acid to produce the salt, while the hydrogen in the acid reacts with the oxygen in the base to produce the water. This is essentially a neutralisation reaction, as metal oxides and metal hydroxides tend to be bases. (Okay, there are some that are amphoteric- can be an acid OR a base depending on the situation- and they have different reactions, but I'll deal with them later.)

Acid + Base -> Salt + Water

Same thing as I said in Reactions and Equations, part deux. I've realised I made a mistake in that post about suggesting that all bases have OH- ions, which isn't true. I'd say use the above 3 equations if they fit the job description, this one's rather vague in comparison.

Base + Ammonium Salt -> Ammonia + Salt + Water

The cation (positive ion) of the base and anion (negative ion) of the ammonium salt bond to make the salt. Then the N and 3 H of the ammonium ion make the ammonia, leaving behind an H+ ion. This H+ ion bonds with the O(2-) (can't be bothered with superscripts either... too much effort) or OH- ions in the base to make water.

I'll leave the amphoteric metal reactions for another time. TTFN!