Just a Thought.

2 years of 04 has closed with a rather smoky finale(you know what i mean.)

2 years of joy, disappointment, laughter, anger barbecued to perfection on pit C16, in a torrent of rain, wind, noise and smoke. The spirit shown in a short 4 hours showed me what we were as a class. Resilience, determination, to get the BBQ going, Thinking positively, every fibre of one's body praying for the heavens to cease its mood swings. Finding humour in the process as well, no matter how bleak the situation has become.

We need not be in the classroom only then do our qualities as a class shine through. I quote from a magazine : Anytime, Anyone, Anywhere. It matters not where we are at any given moment, we still practice what we preach from the classroom, and to great and absolutely GLORIOUS effect. It is evident from that failed midnight pool game to the bedding problems, It is all for one, one for all. Failed we may have in uniting all 43 people, but for those who choose jump on the ever-enthusiastic bandwagon, you will find we have become more than friends. It is a close-knit family.

Take the cast of Under One Roof for example. they may come from wholly different backgrounds, one is even some bizarre international hybrid, but one look at their tearful goodbyes let you know that they regard themselves as one, as a family, well and truly under one roof. Or even Friends. The inexplicable chemistry is ever present despite dumbing down from showbiz, and is unlikely ever to fade.

Same goes with us, really. We come from all sorts of little nooks and crannies, but we have still all wound up in the little room, a stage to present something we have worked on for 2 whole years, some 4 , even more. Friends are like wine, really. They just get better and more priceless as it matures. From the evidence, we are one hell of a Cabernet. Or a cocktail using some expensive and old booze. Tastes like orange juice, but blows your head off after 2 sips, 'cos there's too much damn goodness in there.


And with hindsight, I think it was really destined to rain. Heaven was crying at what was possibly the biggest, and possibly last(hope not) outdoor gathering of one of the best families in the world, soon to be confined to the dusty vaults of history, never to be seen again. Pity.

But rest assured, the memories will be the polished, shining, pure gold trophy in the centre of the "Bloody Good Times That I Had"cabinet of the big grey blob in our skulls. As I quote from "All We Are" by OneRepublic...

So don't say your goodbyes you know its better that way
We won't break, we won't die
It's just a moment of change


We won't die. 404 forever.

p.s. buy 1320 for 4D thanks, split the winnings.


kilodelta

Hot news from AH LEE himself.

Super cool party at his house on tuesday.

booze,drugs,music & games.

All invited to come.

Girls preferred.

Hello all, been a while since i've posted anything decent, so here's the heads up, the chalet will be held on 4th to 6th December, this coming tuesday to thursday. We will most probably be meeting at hougang interchange on tuesday afternoon at approximately 1-2pm, if you happen to be interested to meet us first you can contact either me or shirleen. I will be ordering the food from a bbq caterer and depending on the attendance i will collate the total amount of money and splitting it accordingly, and do indicate if you are going for the barbeque session, but it'll be a great session to catch up, so please do turn up for it. I roughly estimate that each person will be paying about 20dollars for the food and chalet, might be lesser depending on attendance. Okay, so moving on i'll be talking about what to bring and what we might most probably be doing.

I reckon its the same shit, though i'll plan it out first to make things flow more efficiently, cause if its free and easy we'll most probably end up doing nothing. So for the first day i think we'll be settling down in the afternoon, do some catching up before we go for dinner together, before we'll go back to the room for some mahjong or dvd session ( this, i need a laptop or something ). After that we'll most probably be going for night cycling and a movie session, and then supper. We'll be walking back though.

So the very next day it'll be a breakfast session, before we head back to decide which group heads to escape and wild wild wet, i'm quite scared of heights though but its worth the scare occasionally. Then we'll maybe have a game of soccer or something, long time since we had a game together. Finally, the bbq. I've yet to grill food for a long time, so im quite looking forward to this one. Will play some stupid games in the meanwhile, with forfeits! After that you guys can go for some pool or arcade session.

And finally we end if off by having talking throughout the night, before we get some sleep and end this chalet. Breakfast the next day, maybe.

I know the activities sounds a little predictable, but the main purpose is after all to gather and talk about whats going on in our lives. After all we hardly have time now that most of us are either working or overseas, so its a good opportunity to reminisce what we've done for the last few years.

Bring all the shit you think we can possibly do, like cards, mahjong set, laptop or dvd player, to spice up the chalet. We're gonna have a live gig by weijin cos he just got his electric guitar, and i dont mind singing. After all its what i do when im really bored. See you people at the chalet!

Now, do remember to bring the basic toiletries like toothbrush, soap and a towel. Not to forget a lot of t-shirts, bermudas and undies. Just in case you get smashed by some cake or drenched with soda. Do take care of your own stuffs. Any help do hit me up @ 98297424, or alternatively contact shirleen if you want to meet us on tuesday. Take care y'all, peaceeeeeeeeeeeeeeeeeeee.

26112007

Hey dudes, sorry to say, but I won't be in school to collect notes on 29th November.

So the confirmed period I would be in school to collect is from 30 November to 2 December. =) Please take note orh.

22112007(1)

Hey hunks and babes!!

I just sold my textbooks and worksheets for $20 bucks cos they were about 100kg in total!

I was just so OMG-ly surprised and stunned. LOL.

Urmz.. I think the place is somewhere at AMK.. That industrial region.. =)

22112007

Hey people, please take note of the following:

CL and HCL students please tidy up your Chinese notes with all the model essays and notes and whatnot and pass to me. I'll be in school from 29November to 2December for SL Camp, so you can come and pass it to me. If you wrote any essay whatsoever, file it in and pass to me too. If you need your file back, I'll pass it to you when we get our results back next year. =)

Remember to give me as many stacks of the notes as you have, especially those which have school stamp. =)

Sorry to bother~

Hi everyone, i so dam free now im gonna mod the blog skin.

firstoff i'll some ideas of words/phrases that can be placed on the class photo (which will be the main part of the skin)

13112007

WOW! LJ you actually attempted to?!?!

I thought your momo doesn't allow cos.. like what you told us yesterday?

*ponders*

Anyone has any good idea as of how to get rid of the books and worksheets and stuff?

Oh yeah. Remember to report to school by 9am this Friday (16 November) to get your report book. LOL.

Prepare tissues for your friends if necessary. LoL.

IF GUYS WANT TO BURN UR BOOKS/PAPERS, THINK AGAIN (ESPECIALLY IN THE TOILET)

I TRIED IT JUST NOW BUT ENDED UP SMOKING UP THE WHOLE HOUSE, THEN I HAD TO SPENT A WHOLE HOUR CLEANING THE TOILET OF WET PAPER - BECAUSE THEY DUN BURN WELL. AS WELL AS CLEARING THE LIVING ROOM OF SMOKE.

This is a friendly public service announcement brought to you by LJ

Stay Safe.

Prom

For those who have yet heard about it,

Mr. Ang would not be attending prom.

Sup guys, class chalet's on the 4-th to 6th december. If you're going, do brnig an extra sum of money as we will be splitting the cost of the chalet among everyone. Activities will be planned for you guys, make it a good closure. Take care y'all.

Jian Wei

06112007

CHECK THIS OUT!!

05112007

Dedicated to Mr. Phua and the lukewarm prata victim:

Muahaha..

On a random note, while I was editing the picture above, a bee flew into the living room..

..after a couple of buzzes..

..PLACK!

....the bee flew into the fan, and got cut up by the blades.

Mind you, the fan speed was the fastest it could go.

-.-

Sianed, i just killed a lizard and its like bothering me so much.

feels like i actually killed a human or something.
stupid lizard was crawling along the sink and i scared it into the knife holder.
then i pour boiling water into the knifeholder then it fell out and scurried to the utensil holder.

then i cocked the air gun and bam.

hit it smack on the right forehead. it twitch and crawled back below the knifeholder (its on the wall). then it lay there in the warm water.

then it bled. red blood.

fucking red blood.

Something interesting to share

A few days back, I stumbled upon some videos that is interesting and be helpful in our future, so I decided to share it with the entire class.

Sliced Bread - Seth Godin



In a world of too many options and too little time, our obvious choice is to ignore the ordinary stuff. Marketing guru Seth Godin spells out why, when it comes getting our attention, bad or bizarre ideas are more successful than boring ones. And early adopters, not the mainstream's bell curve, are the new sweet spot of the market.

Why Are We Happy? Or Not? - Daniel Gilbert



Dan Gilbert is a psychology professor at Harvard, and author of Stumbling on Happiness. In this memorable talk, filmed at TED2004, he demonstrates just how poor we humans are at predicting (or understanding) what will make us happy. (Recorded July 2005 in Oxford, UK. Duration: 22:02)

Some jokes

Vampire Bats

A vampire bat came flapping in from the night, face all covered in fresh blood and parked himself on the roof of the cave to get some sleep.

Pretty soon all the other bats smelt the blood and began hassling him about where he got it. He told them to piss off and let him get some sleep, but they persisted until he finally gave in.

OK, follow me, he said and flew out of the cave with hundreds of bats behind him. Down through a valley they went, across a river and into a huge forest.

Finally he slowed down and all the other bats excitedly milled around him tongues hanging out for blood.

"Do you see that large oak tree over there?" he asked. "YES, YES, YES!!!!" the bats all screamed in a frenzy.

"Good!" said the first bat, "Because I fucking didn't"

A Blonde's Year in Review

January - Took new scarf back to store because it was too tight

February - Fired from pharmacy job for failing to print labels...HELLOOO!...bottles won't fit in printer.

March - Got really excited...finished jigsaw puzzle in 6 months....box said "2 - 4 years"

April - Trapped on escalator for hours...power went out.

May- Tried to make Kool-Aid - wrong instructions... 8 cups of water won't fit into that little packet.

June- Tried to go water skiing - couldn't find a lake with a slope.

July - Lost breast stoke swimming competition...learned later, the other swimmers cheated, they used their arms.

August- Got locked out of my car in a rain storm...car swamped because soft-top was open.

September- The capital of California is "C", isn't it?

October- Hate M&M's - they are so hard to peel.

November - Baked turkey for 4 1/2 days...instructions said 1 hour per pound and I weigh 108 !!!

December - Couldn't dial 911- duh - there's no eleven on the stupid phone.

Salesman

A little old lady answered a knock on the door one day, only to be confronted by a well-dressed young man carrying a vacuum cleaner.

Good morning," said the young man. "If I could take a couple of minutes of your time, I would like to demonstrate the very latest in high-powered vacuum cleaners."

"Go away!" said the old lady. "I haven't got any money!" and she proceeded to close the door. Quick as a flash, the young man wedged his foot in the door and pushed it wide open.

"Don't be too hasty!" he said. "Not until you have at least seen my demonstration." And with that, he emptied a bucket of horse shit onto her hallway carpet. "If this vacuum cleaner does not remove all traces of this horse shit from your carpet, Madam, I will personally eat the remainder."

The old lady stepped back and said, "Well I hope you've got a damned good appetite, because they cut off my electricity this morning."

Cop On Horse

A City cop was on his horse waiting to cross the street when a little girl on her new shiny bike stopped beside him. "Nice bike," the cop said "did Santa bring it to you?" "Yep," the little girl said, "he sure did!" The cop looked the bike over and handed the girl a $5 ticket for a safety violation.The cop said, "Next year tell Santa to put a reflector light on the back of it."

The young girl looked up at the cop and said, "Nice horse you got there sir, did Santa bring it to you?" "Yes, he sure did," chuckled the cop. The little girl looked up at the cop and said, "Next year tell Santa the dick goes underneath the horse, not on top."

19102007

The answers for the Physics June Paper is still saved in this class blog account, but you have to sign in to see it.

Things to note for O Level Exam:

1. ENTRY PROOF

2. Avoid bringing GARGANTUAN pencil cases

3. Remember to remove any bits and pieces of paper/formula sheet from your pencil cases and calculator

4. Report punctually

5. Bring extra pens and whatnot

6. Usage of correction tape is merely not advisable

7. Remember to use only dark blue/black pens

8. Bring mathematical set(s) for Maths, Sciences, Geography

9. Bring string for Geography Paper one if you're scared.

10. Bring extra calculator/battery

11. Bring Water bottle

12. Don't burn midnight oil the night before the paper

13. Take good care of your health

14. Remember to read instructions to know how many questions to attempt.

15. Lastly, remember that asking question is Free of Charge.

16102007

Hello people once again!

Mr. Chee gave some of us the answer scheme for the June 2007 Physics paper.

You can get it from him to photocopy a copy for yourself, or look for either Ginny, me, Hui Jing, Cheryl, Jian Wei, Cun Kuang, Kah Meng, Yie Sing, Cassandra, Sandra, Shi Ling, Evelyn, Chin-Wen or Yeong Jing as we have the copy too.

I know that the answers to the essay questions weren't printed, but that's only because our nice teacher didnt give me the answer sheet. Lol. I'll post the answers to the essay questions here this Thursday, so do remember to come and check, and inform your friends too.

The following are the answers for the MCQs.

1. A
2. B
3. C
4. B
5. D
6. A
7. D
8. D
9. A
10. C
11. C
12. D
13. A
14. B
15. B
16. A
17. B
18. B
19. B
20. C
21. D
22. C
23. A
24. B
25. C
26. A
27. D
28. B
29. D
30. C
31. D
32. C
33. B
34. A
35. D
36. D
37. C
38. D
39. B
40. A

Those who got the answers from Mr. Chee earlier on are to note that there is a change in answer for question 37, the correct answer is C instead of B.

The answers are supposedly correct as they are done by our teacher. ^_^

I'm not responsible for any mistakes horh.

On the other hand, I've compiled notes without any diagrams for Weather Studies for each of the weather elements separately, namely Humidity, Temperature, Air Pressure, Rainfall and.. something else lah. Oh. Winds... and also done a compiled note for River Studies.

You can ask Mrs Wong, Yeong Jing or me to email them to you. Wahaha. FOC leh!!

14102007

Here's the Summarized notes for Rivers.

Our FT once told us that it's important to note that it's getting less common for requirement of drawing diagrams. So do take note of it lest you have yet realised.

Then urmz.

The tidied notes are supposedly typed in Microsoft Word, but I dunno how to upload MWD onto blog (not like it's possible, i think) so the following is the best I could do lo.

If you want to print it out that badly, sms me or tag and I'll email it to you asap. Please tell me your email address, of course.

ALRIGHT PEOPLE!!!
THANKS TO YAP NING
WE'RE GG TO HAVE A CLASS CHALET THIS YEAR
BUT WE HAVEN'T GOT ANY FURHER DETAILS ABT IT
BUT WE WILL BE HAVING ONE!
I INSIST!

SHALL GO INTO A SERIOUS DISCUSSION WHEN THE O'S OVER~
BYEBYE
TAKKAIRE
CYA PEEPS!
STUDY HARD!

welfare head, LYJ

Notes on migration

TYPES OF INTERNATIONAL MIGRATION

Examples of different types of international migration

	Forced	Voluntary
LEDC to LEDC	Movements of Hindus and Muslims after the Partition of India Migration of Ethiopians into Sudan	Labour recruitment in Venezuela Indian labour to Trinidad
LEDC to MEDC	Expulsion of Asians from Uganda Evacuation of Tristan da Cunha	Turkish guest workers in Germany West Indian migrants to UK
MEDC to MEDC	Emigration of Jews from Germany Refugee movements in former Yugoslavia	Movement of Soviet Jews to Israel Retirement moves from UK to Spain
MEDC to LEDC	British penal settlements in Australia Pilgrim Fathers to USA	White settlers to British colonies Japanese branch plant staff in Indonesia

Do you think that the rural – urban distinction is important in international migration as well as national migration?

Impact of international migration

POSITIVE	NEGATIVE
COUNTRY OF DEPARTURE (SOURCE)
Relief of shortages eg food, housing, jobs, services Reduced pressure on resources Emigrants send money back to relatives Increased influence / awareness overseas If migrants return, they take new skills back with them Reduction of birth rate in overpopulated areas due to emigration of people of child-bearing age	Loss of human resources eg labour, enterprise, skills Communities and regions drawn into vicious circle of decline Growth of emigration culture Dependence on remittances Premature ageing of population due to emigration of younger people
COUNTRY OF ARRIVAL (HOST)
Enrichment of human resources i.e. enterprise, skills, capital Cultural diversification and emergence of a more multi-ethnic society Unwanted jobs filled by cheap labour Opening up of peripheral regions	Pressure on food supplies, housing, jobs, services, etc Discrimination against immigrants, particularly if members of ethnic minorities Congestion, particularly in major cities Spread of disease Predominance of males leading to social problems

Different types of government-led migration

Motives	International migration	Internal migration
Political	US selective immigration Expulsion of Ugandan Asians Vietnamese boat people	Israeli settlement of West Bank China’s Cultural Revolution Westminister Council’s displacement of tenants
Social	Manx policy to attract wealthy immigrants Export of UK orphans to colonies in the 19thC	Post-war overspill in UK Kibbutz movement in Israel
Ethnic / Religious	Evacuation in Ethiopian Jews Immigration control in UK Partition in India	Apartheid in South Africa Ethnic cleansing in former Yugoslavia Movement of Kurds in Iraq
Economic	Labour recruitment in Venezuela Australia’s populate or perish policy Turkish guest-workers in Germany	Ethiopian villagisation Indonesian transmigration Control movement in Romania

07102007

SORRY 404..

That I've been keeping the photos of our class in my computer and not sharing them with you guys.. Reckon that I got too paranoid lest the photos are abused/misused..

But I just watched the CD CK gave us..

..and I decided that I'll send ALL the photos I have of you guys to ALL of you in the near future, for memories' sake. Hope that you guys would remember the memories woven with every classmate, and preserve the friendships, if not building on.

There's a saying that Things left unsaid would eventually become regrets of the future..

Hope that you guys would not leave anything unsaid to any other classmate in class.. Keeping them to yourself would not bring your message across in time before graduation.. Let there be no regrets.. =)

Meanwhile, do remember to work hard in these last 14 days we have left until O Levels. =)

On the other hand, please make sure that you get the Physics Other Schools papers (Anderson, Bukit Panjang, CHIJ, Crescent Girls..) from me TOMORROW after your Chemistry lesson. In addition, you'll be getting a note on Physics Practical which I hope would benefit you guys.

Don't worry, you don't have to pay for the additional sheet of "tips". =)

So from now, feel free to download the photos put up by me in Friendster or anywhere else to keep for yourself. =)

Once again, good luck, people, for O Levels in advance.

~Emo-ing Hui Ying~

P.S.: Oh yeah, remember to pay twenty cents tomorrow for your Chem Notes.

gosh i love indians

CLASS VENT SERVER

Hi guys, im hosting a Ventrilo server. If you dun noe what it is, its a program that allows conference calls/mass chats.(FREE?!) Its very small and has relatively high quality (compared to skype to msn) my current license only allows me to host a max of 8 but i think thats good enough.

http://www.ventrilo.com/download.php

click on the i386-32bit version, download and install :)

after installing, run it.

First enter, your username, by clicking the arrow next to the username blank and jsut type and name u like.

Then click on the arrow button next to the server box.

then enter the following items:

ip:58.182.107.29
port:3784
password:rapture

after u've done this click connect and u should urself in my server

Next we will set up the voice options.

click setup.

tick teh push the talk option

then designate the key and u are ready to go!

more details later on

03092007

Class blog dying soon! Can someone else besides Hui Ying pls pls pls blog?

Can someone VOLUNTEER to change class blogskin also?

LINKS UPDATED?

MISSED OUT ANYONE?

YES? NO?

24072007

Our class didn't sing Jasmine a birthday song today--

Happy birthday to you~

Happy birthday to you~

Happy birthday to Jasmine~

Happy birthday to you~

How many people in our class have yet embraced NC-16?

19072007(1)

After this morning's incident..

Hope that you guys would participate actively for next Monday's event, and try to wear Ethnic Costumes. =) The following are a few I have which you guys may want to borrow to wear, and I'll try to find the rest if I have the time. Only the white one is for guys, the others are girls'.

~Huiying~

19072007

Hello people!
The following is the Prelim Exam Time Table Miss Chan showed Band 2B today..
I'm not sure about the Chemistry and Combined Science dates and times, so this is just a tentative copy that would probably prepare you in advance.. =)

The following is the Self-Study Programme schedule WITH the respective dates so that you can pack your bag with lesser confusion. Hope it helps! ^_^

~Huiying~

Testing

The following are Organic Chemistry notes Mrs Ng sent to Ginny some time ago, which you guys may want to download and print. If you can't print it just because it is in bitmap format and you want the Microsoft Word softcopy, SMS me to ask for it or ask Ginny to send to you.

When you download, the pictures are in order, titled from Page 1 to Page 8. Please check that you do not miss out any of the pages lest your notes become incomplete.

On the side note, save paper, by printing on both sides of the paper. =)

~3cho3YingZoo7.

Yellow booklet answers page 120 – 152 (last page of yellow booklet)
(Air, Water, The Haber Process, The Contact Process)

Air (page 120 – 131)
Pg 120
1. mixture, nitrogen, 79%
2. Noble gases, argon
3. glowing
4. B

Pg 121
5. A
6. B
7. B
8. B

Pg 122
9. C
10. B

Pg 123
1. fractional distillation, expansion, boiling points
2. carbon dioxide, soot, carbon monoxide
3. energy, water vapour, carbon dioxide
4. C
5. D

Pg 124
6. a) Incomplete combustion produces soot (carbon), carbon monoxide and water vapour;
carbon monoxide is poisonous
b) (i) respiration
(ii) glucose from foodstuff
c) (i) welding (using oxyacetylene flame)
(ii) carbon dioxide and water vapour
7. a) 79%, 20%
b) (i) presence of ice (from water vapour) will result in b.p. elevation of other liquefied gases; prevent blockage of the pipes by solid carbon dioxide and ice
(ii) nitrogen, argon, oxygen and krypton

Pg 125
1. carbon monoxide, unburnt hydrocarbons

Pg 126
2. oxides of nitrogen
3. incomplete
4. sulphur, sulphur dioxide, sulphurous acid (H2SO3)
5. ozone
6. nitrogen, carbon dioxide
7. desulphurization
8. D
9. A
10. A

Pg 127
11. a) methane
b) sulphur dioxide
c) ozone
d) unburnt hydrocarbons / carbon monoxide / nitrogen oxides
e) sulphur dioxide
f) nitrogen oxides

12. a) reacts with water vapour and oxygen in the atmosphere, forming acid rain, which corrodes buildings and destroys crops
b) (i) Mg(OH)2 + SO2 à MgSO3 + H2O
(ii) Neutralization
c) (i) MgSO3 à MgO + SO2
(ii) Manufacture of sulphuric acid in the Contact Process
(iii) Recycled / reused to absorb more sulphur dioxide

Pg 128
13. a) From secondhand smoke
b) Vol = 0.01% of 10 dm3 = 1 cm3
c) Incomplete combustion from the cigarette
d) Non-smoker
e) Forms carboxyhaemoglobin in blood, prevent transport of oxygen hence breathing difficulty.

Pg 129
carbon cycle
combustion, photosynthesis
carbon dioxide
a) CO + O3 à CO2 + O2
b) 2NO + 2CO à 2CO2 + N2
c) Catalytic converters

Pg 130
a) carbon dioxide, water vapour, energy
b) Respiration and combustion use up oxygen, carbon dioxide produced, photosynthesis uses up carbon dioxide, oxygen produced.
c) Melting of polar ice caps à flooding of coastal (low-lying) areas
Decrease in crop yields à desertification

Pg 131
a) (i) Incomplete combustion of fuel (petrol)
(ii) carbon dioxide 2CO + O2 à 2CO2
b) (i) 2NO2 à N2 + 2O2 or 2NO à N2 + O2
(ii) reacts with oxygen and water vapour in atmosphere, producing acid rain
c) (i) Substance that speeds up rate of reaction without forming products or used up (i.e. no chemically involved).
(ii) The purpose of the catalysts is different thus use of catalyst is different.
a) Ozone layer blocks harmful uv rays responsible for skin cancer. Ozone holes allow passage of uv rays.
b) Source: reaction of unburnt hydrocarbons with nitrogen dioxide in sunlight
Effect: breathing difficulties
c) (i) Try it out yourself. You should be able to draw the covalent molecule.
(ii) HFCs do not decompose, when exposed to sunlight, forming free radicals

Water (page 132 – 137)
Pg 132
anhydrous, white, blue
mineral salts
phosphates
eutrophication
D
D

Pg 133
a) (i) Atoms of same element with different mass numbers
(ii) H-1 : 1 proton, 0 neutron
H-2 : 1 proton, 1 neutron
b) (i) Helium does not react with oxygen / Mixture of H2 and O2 explodes with small sparks
(ii) Reaction of H2 and O2 very exothermic, great deal of heat produced to propel rocket / No reaction between helium and oxygen.

a) Compound: Formed from chemical reaction, 2 or more different substances chemically combined
Exothermic: Reaction in which (heat) energy is given out / produced
Elements: Substances that cannot be further decomposed into anything simpler
b) 2H2 + O2 à 2H2O
c) You should be able to draw the energy profile diagram on your own. It’s an exothermic reaction so the energy level of products is lower than the energy level of reactants.

Pg 134
Chlorine
activated carbon
desalination
a) filtration – to remove fine suspended solid particles
chlorination – to kill harmful bacteria

Pg 135
4. b) (i) Sea water
(ii) Nitrate
(iii) Distillation
c) (i) Salt
(ii) Desalination
d) Test 1: White anhydrous copper (II) sulphate à blue
Test 2: Blue cobalt (II) chloride paper à pink

Pg 136
5. a) (i) D
(ii) B
(iii) Na2SO4, NaNO3, Ca(NO3)2 but not CaSO4 (insoluble)
(iv) A. High concentration of sulphate ions and nitrate ions found in fertilizers.
b) 4Fe2+ (aq) + 4H+ (aq) + O2 (g) à 4Fe3+ (aq) + 2H2O (l)
How to do it???
1) Write out the reactants, ions, compounds, etc involved.
2) Balance the number of ions / atoms / etc on each side of the equation
3) Check to ensure that the overall charge on each side of the equation is the same. The charges do not necessary have to add up to 0 on both sides.

Pg 137 (Crossword puzzle)
1) Ammonia
2) Anhydrous
3) Sodium
4) Margarine
5) Extinguished
6) Drink
7) Kitchen
8) Neutral
9) Lighted
10) Decompose
11) Explosion
12) Natural
13) Liquid
14) Distillation
15) Non

The Haber Process (page 138 – 146)
Pg 138
alkaline, moist, blue
ammonium, alkali

Pg 139
Haber, 200, 450°C
reversible
A
B
D
D

Pg 140
a) Increase pressure, increases %NH3
b) (i) 27%
(ii) Advantage: Low temp makes reaction slow. Hence at 450°C, reaction proceeds faster than at 350°C.
Disadvantage: At same pressure, %NH3 at 450°C is lesser than %NH3 at 350°C.
c) Catalysts are not used up in the reaction and can be recycled.
d) Moist red litmus turns blue in ammonia.
Lighted splint extinguished with ‘pop’ in hydrogen.
Glowing splint rekindled in oxygen.

Pg 141
proteins
eutrophication
nitrogen

Pg 142
C
D
B
A
a) %N in NaNH2 = 35.9% (to 3 s.f.)
Mass required to produce 14 tonnes nitrogen = 39

%N in (NH2)2CO = 46.7% (to 3 s.f.)
Mass required to produce 14 tonnes nitrogen = 30

Thus urea (NH2)2CO provides more nitrogen per tonne of fertlizers.

Pg 143
8. b) High solubility of nitrate ions washed into nearby rivers (leaching); growth of algae in rivers encouraged; algae dies and decays, oxygen is used up; oxygen content depleted / decreased

c) (i) 2NH4NO3 + Ca(OH)2 à Ca(NO3)2 + 2H2O + 2NH3
(ii) Reduce acidity of soil
(iii) Calcium hydroxide reacts with ammonium nitrate, producing calcium nitrate which is a neutral salt, water and ammonia.
Nitrogen is displaced from fertilizers, and not used to increase nitrogenous content of the soil; thus wasted.

Pg 144
9. a) (i) 2850 kg (estimated from half of (2600 kg + 3100 kg))
(ii) From 20 kg of phosphorus added onward, very slight increase to potato yield per kg.
b) (i) Mr of Ca(H2PO4)2 = 234
(ii) %P in Ca(H2PO4)2 = 26.5% (to 3 s.f.)
Mass to be provided = 56.6 kg (to 3 s.f.)
(iii) Potassium nitrate, KNO3

Pg 145
10. a) Necessary for plant growth and repair of plant cells (synthesis of proteins)
b) 2NH3 + H2SO4 à (NH4)2SO4
c) %N in NH4NO3 = 35%
%N in (NH4)2SO4 = 21.2%
%N in urea = 46.7% (highest %N by mass)
d) You should be able to draw the covalent molecule of ammonia. If not, please check your textbook.

Pg 146 (Fun with Chemistry)
UREA
POTASSIUM
CHLOROPHYLL
AMMONIUM NITRATE
PROTEIN
BACTERIA
LIME
NITROGEN
TRACE ELEMENTS


The Contact Process (pg 147 – 152)
Pg 147
S8, low, yellow
sulphur dioxide, pungent, acid rain
preservative, bleach
D

Pg 148
SO2, vanadium (V) oxide, 450°C, 1 atm
water, sulphuric acid, oleum
fertilizers
C

Pg 149
C
E
D
B

Pg 150
a) Manufacture of fertilizers
b) Sulphuric acid with barium nitrate solution; white precipitate of barium sulphate produced
c) (not in graph) As an electrolyte in car batteries / making of detergents
d) Reaction: H2SO4 + MgCO3 à MgSO4 + CO2 + H2O
Observation: Effervescence / bubbles of gas produced
Products: magnesium sulphate, carbon dioxide and water

10. a) (i) Ammonium sulphate
(ii) Plants need other elements (like potassium and phosphorus) for healthy growth, thus other fertilizers needed to provide the K and P.

Pg 151
10. b) (i) 3H2SO4 + Fe2O3 à Fe2(SO4)3 + 3H2O
(ii) Acid will react with iron in steel sheets.
c) (i) 2SO2 + O2 2SO3
(ii) 450°C, 1 atm, with vanadium (V) oxide as catalyst
(iii) Sulphur dioxide gains oxygen, forming sulphur trioxide, thus oxidation (gain of oxygen) OR
Increase in oxidation state of sulphur from +4 to +6 thus oxidation.
d) (i) Use of sulphur dioxide: as a food preservative;
as a bleaching agent for wood pulp
(ii) Add / pass / bubble gaseous compound into
1. acidified potassium dichromate (VI) solution; turns from orange to green
2. acidified potassium manganate (VII) solution; turns from purple to colourless

Pg 152 (Fun with Chemistry)
1. sulphide
2. sulphurous
3. electrolyte
4. pickling
5. hydrogen
6. anhydride
7. trioxide
8. fertilizers (end of yellow bookle

Orgnic Chemistry

Organic Chemistry Class 401 / 404

Important terms you should know:
1. addition reaction (TB pg 425)
Reaction in which a molecule (element or compound) adds to an unsaturated compound to form a single new compound (referred only to alkenes).

2. cracking (TB pg 428)
The breaking down of long chain hydrocarbon molecules with heat and/or catalyst to produce smaller hydrocarbon molecules or hydrogen.

3. fermentation (TB pg 436)
The conversion of glucose (or simple sugars) by yeast into carbon dioxide and ethanol.

4. functional group (TB pg 416)
An atom or group of atoms that gives characteristic properties to an organic compound.

5. homologous series (TB pg 418)
Family of organic compounds with same general formula (same functional group), having similar chemical properties, showing slight gradation in the physical properties, and having each member differ from the next by a –CH2 unit.

6. hydrocarbons
Organic compounds made up of the elements hydrogen and carbon only.

7. polymerization (TB pg 449, polymers)
Chemical reaction in which simple molecules (called monomers) react with each other to form large molecules (called polymers).

8. saturated
Containing single covalent bonds in its carbon atoms only.

9. unsaturated
Containing one or more double covalent carbon-carbon bonds.
(polyunsaturated means containing more than one / many double carbon-carbon covalent bonds.)

10. esterification (TB pg 443, ester)
Chemical reaction between an alcohol and a carboxylic acid, using concentrated sulphuric acid as catalyst, to produce esters (sweet smelling liquids).


Alkanes
Alkenes
Alcohols
Carboxylic acids
Definition
(n : number of carbon atoms)
Saturated hydrocarbons having the general formula CnH2n+2.
Unsaturated hydrocarbons having the general formula CnH2n.

(functional group C=C)
Organic compounds containing the hydroxyl group, -OH, with general formula CnH2n+1OH.
Organic acids containing the carboxyl group, -COOH, with general formula, CnH2n+1COOH, where n starts from zero.
First five members
(names and chemical formula)
Methane, CH4
Ethane, C2H6
Propane, C3H8
Butane, C4H10
Pentane, C5H12
Ethene, C2H4
Propene, C3H6
Butene, C4H8
Pentene, C5H10
Hexene, C6H12
Methanol, CH3OH
Ethanol, C2H5OH
Propanol, C3H7OH
Butanol, C4H9OH
Pentanol, C5H11OH
Methanoic acid, HCOOH
Ethanoic acid, CH3COOH
Propanoic acid, C2H5COOH
Butanoic acid, C3H7COOH
Pentanoic acid, C4H9COOH
Physical properties
(Trends exhibited down the group)
1. Melting point and boiling point increases.
2. Viscosity and density increases.
3. Less flammable; smokier smoke produced.
1. Melting point and boiling point increases.
2. Viscosity and density increases.
3. Less flammable; smokier smoke produced than alkanes.
1. Melting point and boiling point increases (first 4 members are liquids at rtp).
2. Solubility decreases.

1. Melting point and boiling point increases.
2. Solubility decreases.



Alkanes
Alkenes
Alcohols
Carboxylic acids
Chemical properties
1. Complete combustion gives carbon dioxide and water vapour as only products.
2. Incomplete combustion produces carbon (soot) and/or carbon monoxide and water vapour.
3. Substitution reactions occur with halogens (F2, Cl2, Br2) in uv light.


Alkanes are generally unreactive due to their saturation.
1. Complete combustion gives carbon dioxide and water vapour as only products.
2. Incomplete combustion produces carbon (soot) and /or carbon monoxide and water vapour.
3. Undergo addition reactions with
Ÿ hydrogen (hydrogenation; making of margarine);
Ÿ bromine (bromination; test for unsaturation);
Ÿ steam (production of alcohols) and
Ÿ other alkenes (polymerization)
1. Complete combustion gives carbon dioxide and water vapour as only products.
2. Oxidation
Ÿ In lab using acidified K2Cr2O7 forming carboxylic acid.
Ÿ By exposure to air (oxygen), forming carboxylic acid, due to action of bacteria in air.
3. Esterification with carboxylic acid, producing esters and water.
1. Complete combustion gives carbon dioxide and water vapour as only products.
2. Weak acids, having same chemical reactions as inorganic acids with reactive metals, bases and carbonates.
3. Esterification with alcohols, producing esters and water.
Source
1. Crude oil / petroleum
2. Cracking of larger hydrocarbons
1. Crude oil / petroleum (minor source)
2. Cracking of larger hydrocarbons
1. Catalyzed addition of steam to alkenes
2. Fermentation of simple sugars (glucose)
1. Oxidation of alcohols by
Ÿ acidified K2Cr2O7
Ÿ bacteria in air


Alkanes
Alkenes
Alcohols
Carboxylic acids
Uses
1. As a fuel.
1. To form plastics through addition polymerization.
1. As a fuel.
2. As a solvent.
3. To make alcoholic beverages.
4. To form esters.
1. To form esters.
Website for reference: http://www.chemguide.co.uk/orgpropsmenu.html

Important chemical reactions
Brief description
Conditions
Products
Chemical equations / Observations (if any)
Alkanes
Substitution with halogens
(using methane to illustrate)
Presence of uv light;
F2 / Cl2 / Br2
(with chlorine)
Mixture of chloromethane (CH3Cl); dichloromethane (CH2Cl2); trichloromethane (CHCl3); tetrachloromethane (CCl4); and hydrogen chloride (HCl)
CH4 + Cl2 à CH3Cl + HCl
CH3Cl + Cl2 à CH2Cl2 + HCl
CH2Cl2 + Cl2 à CHCl3 + HCl
CHCl3 + Cl2 à CCl4 + HCl
Any or all of the above can occur at the same time.
Reaction stops when methane and/or chlorine are used up.
Alkenes
Addition reaction with hydrogen
(Hydrogenation of ethene)
Approx 200°C;
nickel catalyst;
hydrogen gas
Ethane
Generally, the corresponding alkane is obtained.
C2H4 + H2 à C2H6

Generally, CnH2n + H2 à CnH2n+2


Important chemical reactions
Brief description
Conditions
Products
Chemical equations / Observations (if any)
Alkenes
Addition reaction with bromine
(Bromination of ethene)
Bromine solution
Dibromoethane
C2H4 + Br2 à C2H4Br2
Reddish brown bromine solution is decolourised.
A colourless product is obtained.
This is also known as the test for unsaturation.
Alkenes
Addition reaction with steam
(using ethene to illustrate)
300°C; 65 atm;
phosphoric acid as catalyst
Ethanol
Generally, the corresponding alcohol is obtained.
C2H4 + H2O à C2H5OH

Generally, CnH2n + H2O à CnH2n+1OH
Alkenes
Addition polymerization
(using ethene to illustrate)
High pressure;
high temperature;
catalyst

(1000 atm; 200°C)
Poly(ethene)

Generally, name of polymer is obtained by putting the monomer in brackets and adding ‘poly’ in front of the brackets.
E.g. polymerization of ethene

n CH2 = CH2
ethene poly(ethene)
Catalytic cracking
(for both long-chained alkanes and alkenes)
High temperature; catalyst

(about 600°C; aluminium oxide or silicon (IV) oxide as catalyst - aluminosilicates)
Mixture of short-chained alkenes and mixture of short-chained alkanes or H2 (g)
E.g. hexane à butane and ethene
C6H14 à C4H10 + C2H4
Alternatively, hexane à ethene + hydrogen
C6H14 à 3C2H4 + H2
Products obtained depend on conditions imposed.

The total number of carbon atoms and hydrogen atoms must be the same before and after cracking.


Important chemical reactions
Brief description
Conditions
Products
Chemical equations / Observations (if any)
Alcohols
Oxidation to carboxylic acids
(using ethanol to illustrate)
Oxidizing agent such as acidified K2Cr2O7 or by exposure to air
Ethanoic acid and water

Generally the corresponding carboxylic acid will be obtained.
ethanol + oxygen from O.A. à ethanoic acid + water
C2H5OH + 2[O] à CH3COOH + H2O
Orange acidified potassium dichromate (VI) turns green.

ethanol + oxygen from air à ethanoic acid + water
C2H5OH + O2 à CH3COOH + H2O
A sour liquid is obtained.
Fermentation of simple sugars (glucose)
Enzymes in yeast;
37°C;
simple sugars;
absence of air
Ethanol and carbon dioxide
glucose solution à ethanol + carbon dioxide
C6H12O6 à 2C2H5OH + 2CO2
Carboxylic acids
Reaction with reactive metals
(using ethanoic acid to illustrate)
Reactive metals
(e.g. Na)

The reactivity series of metals applies.
Organic salt + hydrogen gas
(e.g. sodium ethanoate + hydrogen)
ethanoic acid + sodium à sodium ethanoate + hydrogen
2CH3COOH + 2Na à 2CH3COO-Na+ + H2

Effervescence; colourless gas produced, extinguished lighted splint with ‘pop’.
ethanoate ion = CH3COO-


Important chemical reactions
Brief description
Conditions
Products
Chemical equations / Observations (if any)
Carboxylic acids
Reaction with bases / alkalis
(using ethanoic acid to illustrate)
Bases or alkalis
(e.g. NaOH)
Organic salt + water
(e.g. sodium ethanoate + water)
ethanoic acid + sodium hydroxide
à sodium ethanoate + water
CH3COOH + NaOH à CH3COO-Na+ + H2O

This reaction is also called a neutralization reaction.
Carboxylic acids
Reaction with carbonates
(using ethanoic acid to illustrate)
Carbonates
(e.g. Na2CO3)
Organic salt + water + carbon dioxide gas
(e.g. sodium ethanoate + water + carbon dioxide)
ethanoic acid + sodium carbonate
à sodium ethanoate + water + carbon dioxide
CH3COOH + Na2CO3 à CH3COO-Na+ + H2O + CO2

Effervescence; colourless gas produced, forms white precipitate with limewater.
Esterification
(between carboxylic acids and alcohols)
(using ethanoic acid and ethanol to illustrate)
Ethanoic acid;
ethanol;
few drops of concentrated H2SO4 as catalyst;
heat
Ester + water
(e.g. ethyl ethanoate + water)

A molecule of water is always produced when a molecule of carboxylic acid reacts with a molecule of alcohol.
ethanoic acid + ethanol à ethyl ethanoate + water
CH3COOH + C2H5OH à CH3COOC2H5 + H2O

Generally, the –H is removed from the alcohol while the –OH is removed from the carboxylic acid to form the water of molecule produced during esterification.
First part of name of ester comes from the alcohol (from –ol change to –thyl) while second part of name of ester comes from the carboxylic acid (from –oic acid change to ­–ate).


Description
Reaction
Conditions
Products
Structure of product
Esterification
(Formation of ethyl ethanoate)
Heat and few drops of concentrated H2SO4 as catalyst
Ethanol and ethanoic acid
Ethyl ethanoate
(known as esters, which are generally sweet smelling liquids / oils)



Refer to TB pg 442 for structure of ethyl ethanoate
Condensation polymerization of esters
Heat and few drops of concentrated H2SO4 as catalyst
Monomers:
Alcohol and carboxylic acid
Polyesters
Synthetic polyester:
Terylene
Natural polyester:
Fats
Refer to TB pg 456 (Structure of terylene polymer)
Condensation polymerization of amides
Heat and a few drops of concentrated H2SO4 as catalyst
Monomers:
Alcohol and amine
Polyamides
Synthetic polyamide:
Nylon
Natural polyamide:
Proteins
Refer to TB pg 455 (Structure of nylon polymer)
Addition polymerization
of ethene
High pressure (1000 atm); High temperature (200°C);
Catalyst
Monomer:
Ethene
Poly(ethene)
(also called polythene)





Refer to TB pg 450 for structure of poly(ethene) polymer
Refer to TB pg 452 Table 28.2 for details of other common polymers
End of brief notes on Organic Chemistry
© Mrs Annie (XMS Science Dept 2007)