Author Topic: Chemistry P3 7/6/2010  (Read 24428 times)

Offline Dana

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Re: Chemistry P3 7/6/2010
« Reply #105 on: June 06, 2010, 09:06:12 pm »
Um, does this help?:: https://studentforums.biz/index.php/topic,1411.msg254665.html#msg254665
yes it does thank you! so the "negative pole" is actually the anode and vice versa?

Offline Vin

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Re: Chemistry P3 7/6/2010
« Reply #106 on: June 06, 2010, 09:15:38 pm »
yes it does thank you! so the "negative pole" is actually the anode and vice versa?

See, in a cell there is nothing called anode or cathode. Like I mentioned, just -ve and +ve poles. If you see you regular AA/AAA batteries have + and -, it is the same here.

An anode forms when an electrode is given the +ve charge, and -ve charge for cathode.

Here The +ve and -ve charges are produced.

Always in a cell the more reactive metal is the -ve terminal as it is the source of e-.

Offline Dana

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Re: Chemistry P3 7/6/2010
« Reply #107 on: June 06, 2010, 09:19:50 pm »
See, in a cell there is nothing called anode or cathode. Like I mentioned, just -ve and +ve poles. If you see you regular AA/AAA batteries have + and -, it is the same here.

An anode forms when an electrode is given the +ve charge, and -ve charge for cathode.

Here The +ve and -ve charges are produced.

Always in a cell the more reactive metal is the -ve terminal as it is the source of e-.
thank you but see here qs 5 b http://www.freeexampapers.us/IGCSE/Chemistry/CIE/2007%20Jun/0620_s07_qp_3.pdf[url]]http://www.freeexampapers.us/IGCSE/Chemistry/CIE/2007%20Jun/0620_s07_qp_3.pdfhttp://
it specifically says anode and cathode :/ is it a cell or electrolysis?

Offline Vin

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Re: Chemistry P3 7/6/2010
« Reply #108 on: June 06, 2010, 09:36:17 pm »
thank you but see here qs 5 b http://www.freeexampapers.us/IGCSE/Chemistry/CIE/2007%20Jun/0620_s07_qp_3.pdf[url=http://]]]http://www.freeexampapers.us/IGCSE/Chemistry/CIE/2007%20Jun/0620_s07_qp_3.pdfhttp://
it specifically says anode and cathode :/ is it a cell or electrolysis?

Um, electrolysis is 5 b)i ans ii. This is something CIE wants to confuse people, you might have never learned about it but you should use your concepts of oxidation and reduction. Something to be oxidised needs to loose electrons, (rusting is a type of oxidation), if you see there is a power supply which provides constant supply of e- which doesn't allow it to rust.


Offline SoONa

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Re: Chemistry P3 7/6/2010
« Reply #109 on: June 06, 2010, 10:21:40 pm »
Metal Nitrate:
(upon heating)

Group 1: Metal Nitrate > Metal Nitrite + Oxygen
Group 2 & Others : Metal Nitrate > Metal Oxide + Nitrogen Dioxide + Oxygen

Metal Hydroxide :
(upon heating)

Group 1 : No Decomposition
Group2 & Others : Metal Hydroxide > Metal Oxide + Water

Metal Carbonate:
(upon heating)

Group 1: No Decomposition
Group 2 & Others : Metal Carbonate > Metal Oxide + CarbonDioxide  


thank u soo much very helpful.. !!!

Offline luv3life

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Re: Chemistry P3 7/6/2010
« Reply #110 on: June 07, 2010, 03:35:53 am »
Leaving for Chemistry Paper 3 now. Very nervous! My paper starts after 1 and a half hours...

Wish me Luck, guys!

Pray for me, and I shall pray for you! :D
:) LiVe LiFe As If EaCh DaY mAy Be YoUr LaSt :)

Offline gaurav95

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Re: Chemistry P3 7/6/2010
« Reply #111 on: June 07, 2010, 03:47:46 am »
going for d xam in an hour.....
If the sky is the limit, then what is space, over the limit?

Offline Dana

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Re: Chemistry P3 7/6/2010
« Reply #112 on: June 07, 2010, 09:28:50 am »
Um, electrolysis is 5 b)i ans ii. This is something CIE wants to confuse people, you might have never learned about it but you should use your concepts of oxidation and reduction. Something to be oxidised needs to loose electrons, (rusting is a type of oxidation), if you see there is a power supply which provides constant supply of e- which doesn't allow it to rust.


thanks :)

Offline The Golden Girl =D

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Re: Chemistry P3 7/6/2010
« Reply #113 on: June 07, 2010, 12:15:18 pm »
yo amigos ...........i hope y'all roast the paper today ,if u kno what i mean :P
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Offline J.Darren

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Re: Chemistry P3 7/6/2010
« Reply #114 on: June 07, 2010, 03:33:14 pm »
yo amigos ...........i hope y'all roast the paper today ,if u kno what i mean :P
You evil meanie -v- Jokes ... Well I had my exam earlier this afternoon, a high A* is guaranteed, sadly no chance of Top in the World nor Brilliance in Hong Kong due to two careless mistakes that I would never concede in unit tests and internal mocks D:
Do not go where the path may lead. Go instead where there is no path and leave a trail.

Offline The Golden Girl =D

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Re: Chemistry P3 7/6/2010
« Reply #115 on: June 07, 2010, 04:21:01 pm »
You evil meanie -v- Jokes ... Well I had my exam earlier this afternoon, a high A* is guaranteed, sadly no chance of Top in the World nor Brilliance in Hong Kong due to two careless mistakes that I would never concede in unit tests and internal mocks D:

lol.....well atleast an A* is guaranteed mate ;)
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Offline J.Darren

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Re: Chemistry P3 7/6/2010
« Reply #116 on: June 07, 2010, 05:35:03 pm »
lol.....well atleast an A* is guaranteed mate ;)
This can be best described as a stinging bitterness, checked thrice with the lab dude and chemistry teacher at school, am very confident that I have gotten every single questions in papers 1 and 5 correctly ... I probably have lost three marks at max in Paper 3, but since my ultimate aspiration is Top in the World, it is a major setback nonetheless ...
Do not go where the path may lead. Go instead where there is no path and leave a trail.

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Re: Chemistry P3 7/6/2010
« Reply #117 on: June 07, 2010, 05:39:49 pm »
This can be best described as a stinging bitterness, checked thrice with the lab dude and chemistry teacher at school, am very confident that I have gotten every single questions in papers 1 and 5 correctly ... I probably have lost three marks at max in Paper 3, but since my ultimate aspiration is Top in the World, it is a major setback nonetheless ...

The past is quite simply; the past. No matter how hard you try the clock cannot be turned backed.

Relish your A* and be ready to put a wide smile on your parent's face. ;)

Offline Helium

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Re: Chemistry P3 7/6/2010
« Reply #118 on: June 07, 2010, 05:49:54 pm »
yo amigos ...........i hope y'all roast the paper today ,if u kno what i mean :P

yup we roasted, heated and burned in air,

and obtained it pure. :D
Aiming for the top

Offline J.Darren

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Re: Chemistry P3 7/6/2010
« Reply #119 on: June 07, 2010, 05:55:28 pm »
yup we roasted, heated and burned in air,

and obtained it pure. :D
You have forgotten to wash it with water prior to roasting in order to remove traces of the solution in percipitation :P
Do not go where the path may lead. Go instead where there is no path and leave a trail.