Author Topic: IG Chemistry Paper 3 discussion  (Read 24531 times)

Offline goin4dakill

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Re: IG Chemistry Paper 3 discussion
« Reply #150 on: June 02, 2009, 03:28:40 pm »
heY everYone,
wat about electrolysis of dilute sodium chloride???
Cathode..........
anode..............
and wat happens to the electrolyte???.....
WaiTinG 4 uR RepLies!!xD!! :o
Dont take my answer for granted..but I wrote..

Cathode: Hydrogen
Anode: Chlorine
And what happens? umm I think i wrote that Sodium Hydroxide was formed.
Dunno, makes sense tho, tell me what u think

Offline bibo the wa7sh

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Re: IG Chemistry Paper 3 discussion
« Reply #151 on: June 02, 2009, 03:34:03 pm »
I dNtThinK so......becoZ iF iTs DiLTuTe then uve Got Hydrogen on the cathode.........and oxygen on the anode becoz its not concentrated!!!!So the ELEcTroLyte wiLL remAin sodium chloride!!! ::)
Check out htis website,,,its got all the explanation oR go youtube nd watch the video!!!
http://chem.lapeer.org/Chem2Docs/chlorine.html

Offline ETCH

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Re: IG Chemistry Paper 3 discussion
« Reply #152 on: June 02, 2009, 03:49:28 pm »
hey does anybody know what were the raw materials of nitrogen & hydrogen????

Offline astarmathsandphysics

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Re: IG Chemistry Paper 3 discussion
« Reply #153 on: June 02, 2009, 03:52:08 pm »
Do you mean the matrial used to make nitrogen and hydrogen?

could be nitrogen from the air and either hydrocarbons or water to make hydrogen. Hydrogen and nitrogen are the raw material used to make ammonia.

Offline magician007

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Re: IG Chemistry Paper 3 discussion
« Reply #154 on: June 02, 2009, 03:53:34 pm »
Nitrogen from air

Hydrogen from Methane and Water reaction

Offline Shogun

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Re: IG Chemistry Paper 3 discussion
« Reply #155 on: June 02, 2009, 03:54:23 pm »
hydrogen:alkanes like butanol
nitrogen:air

anybody wants ans or explainations to answer for the chem exam i can help u guys...

and By the way about the phosphate thingy, u must go with tht hight of precipitate graph, cuz writing the reason which goes like this "it mus be a reactive metal so it could displace sodium, and must be soluble" then i feel its wrong , cuz u didnt go with the question...(this ques is the only ques i mess up in)
one who masters both the pen and paper is indeed a true warrior.

\m/metal head\m/

Offline ETCH

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Re: IG Chemistry Paper 3 discussion
« Reply #156 on: June 02, 2009, 03:56:35 pm »
for nitrogen I said air but for hydrogen I said crude oil since the question said the "raw materials".

Offline Shogun

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Re: IG Chemistry Paper 3 discussion
« Reply #157 on: June 02, 2009, 03:58:52 pm »
By the way . condesation HAS NO DOUBLE BONDS.

the ans is condesation, cuz it simple molecules like water was removed, and it was not such a sunstance tht contain double bonds (ie. alkenes)

hmm... 1)does crude oil come with alkane or  2)u get alkanes from crude oil, i dont know , but if its 1 then im sure ur correct etch
one who masters both the pen and paper is indeed a true warrior.

\m/metal head\m/

Offline sweetie

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Re: IG Chemistry Paper 3 discussion
« Reply #158 on: June 02, 2009, 04:01:47 pm »
hiiiiiiiiii every1
shogun can u tell me the formula u got 4 da phosphate?

all da best 4 da rest of ur xams










Offline bibo the wa7sh

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Re: IG Chemistry Paper 3 discussion
« Reply #159 on: June 02, 2009, 04:03:35 pm »
heY everYone,
wat about electrolysis of dilute sodium chloride???
Cathode..........
anode..............
and wat happens to the electrolyte???.....
WaiTinG 4 uR RepLies!!xD!!

Offline horror

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Re: IG Chemistry Paper 3 discussion
« Reply #160 on: June 02, 2009, 04:07:33 pm »
heY everYone,
wat about electrolysis of dilute sodium chloride???
Cathode..........
anode..............
and wat happens to the electrolyte???.....
WaiTinG 4 uR RepLies!!xD!! :o
Dont take my answer for granted..but I wrote..

Cathode: Hydrogen
Anode: Chlorine
And what happens? umm I think i wrote that Sodium Hydroxide was formed.
Dunno, makes sense tho, tell me what u think
The electrolyte is used up nothing is formed

Offline horror

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Re: IG Chemistry Paper 3 discussion
« Reply #161 on: June 02, 2009, 04:10:44 pm »
hiiiiiiiiii every1
shogun can u tell me the formula u got 4 da phosphate?

all da best 4 da rest of ur xams     










Its K2PO4 :)

Offline horror

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Re: IG Chemistry Paper 3 discussion
« Reply #162 on: June 02, 2009, 04:13:03 pm »
heY everYone,
wat about electrolysis of dilute sodium chloride???
Cathode..........
anode..............
and wat happens to the electrolyte???.....
WaiTinG 4 uR RepLies!!xD!!
Cathode:sodium
anode chloride
electrolyte: used up
+rep me

Offline girl_92

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Re: IG Chemistry Paper 3 discussion
« Reply #163 on: June 02, 2009, 04:13:49 pm »
i wrote alkenes and alcohols
im sure deyr both functional groups bt i dnt know if im ryt about alkenes
hopefully atleast 1 mark for alcohols
it was carboxylic acids n alcohols
some people sleep to dream while othrs wakeup to follow dem im the second type how abt u

Offline Shogun

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Re: IG Chemistry Paper 3 discussion
« Reply #164 on: June 02, 2009, 04:14:51 pm »
hiiiiiiiiii every1
shogun can u tell me the formula u got 4 da phosphate?

all da best 4 da rest of ur xams     










Its K2PO4 :)


lol i got P3PO4 it cant be p2 cuz the valency of p4 is 3
one who masters both the pen and paper is indeed a true warrior.

\m/metal head\m/