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Author Topic: CHEMISTRY PAPER 1 HERE  (Read 37928 times)

Offline aquarian93

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Re: CHEMISTRY PAPER 1 HERE
« Reply #165 on: June 11, 2009, 03:17:43 pm »
Quote from: madee on June 11, 2009, 03:04:46 pm
Quote from: nid404 on June 11, 2009, 03:01:20 pm
Quote from: aquarian93 on June 11, 2009, 02:57:39 pm
and guys doesnt sodium oxide hav a pH above 7 (metal oxide)

den how cum the answer in nov 05, question 17 is C ???

Read the question correctly. Sodium oxide, when in solution it forms OH-ions which give the pH for the solution and changes pH of water(7) to 12
 Hence C
yea srry i rote it according to tht sodium i didnt read the que properly

its K :)
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Q80BOY

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Re: CHEMISTRY PAPER 1 HERE
« Reply #166 on: June 11, 2009, 03:18:03 pm »
hey guys ...

ive got a question from nov 2001

Page 4, Question 6 ...

Neon has 10 e- and Sodium has 11 e- which makes the answer C, but the mark scheme says its D ...

help !!
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Offline girl_92

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Re: CHEMISTRY PAPER 1 HERE
« Reply #167 on: June 11, 2009, 03:20:40 pm »
Quote from: Q80BOY on June 11, 2009, 03:18:03 pm
hey guys ...

ive got a question from nov 2001

Page 4, Question 6 ...

Neon has 10 e- and Sodium has 11 e- which makes the answer C, but the mark scheme says its D ...

help !!
dude it is sodium ion tht means it has already lost one electron this makes it 10 electrons
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some people sleep to dream while othrs wakeup to follow dem im the second type how abt u

Offline aquarian93

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Re: CHEMISTRY PAPER 1 HERE
« Reply #168 on: June 11, 2009, 03:21:43 pm »
Quote from: Q80BOY on June 11, 2009, 03:18:03 pm
hey guys ...

ive got a question from nov 2001

Page 4, Question 6 ...

Neon has 10 e- and Sodium has 11 e- which makes the answer C, but the mark scheme says its D ...

help !!

it has to be D cuz sodium atom has10, cuz Na+ and loses one electron. so 8 on the outer and none on the last.
neon has to hav complete shells cuz its gr.8
hope i helped
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Offline sundars

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Re: CHEMISTRY PAPER 1 HERE
« Reply #169 on: June 11, 2009, 03:22:23 pm »
Its D since sodium ion is asked.
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Q80BOY

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Re: CHEMISTRY PAPER 1 HERE
« Reply #170 on: June 11, 2009, 03:23:13 pm »
ooooh, i didnt read the ion, i thought it was atom  :-[

silly me !!  :P

thanks for all the help guys  ;)
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Offline aquarian93

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Re: CHEMISTRY PAPER 1 HERE
« Reply #171 on: June 11, 2009, 03:23:29 pm »
guys i need help wid May 06, no. 29
y is it D? doesnt chrome plated keyring, rust?
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Re: CHEMISTRY PAPER 1 HERE
« Reply #172 on: June 11, 2009, 03:24:55 pm »
Quote from: aquarian93 on June 11, 2009, 03:23:29 pm
guys i need help wid May 06, no. 29
y is it D? doesnt chrome plated keyring, rust?
No, that's the whole point, chromium is resistant to corrosion. That is why stainless steel (which contains chromium) is used to plate cutlery.
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Offline aquarian93

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Re: CHEMISTRY PAPER 1 HERE
« Reply #173 on: June 11, 2009, 03:25:43 pm »
Quote from: i-insane on June 11, 2009, 03:24:55 pm
Quote from: aquarian93 on June 11, 2009, 03:23:29 pm
guys i need help wid May 06, no. 29
y is it D? doesnt chrome plated keyring, rust?
No, that's the whole point, chromium is resistant to corrosion. That is why stainless steel (which contains chromium) is used to plate cutlery.

oh ok so its nthng to do wid da experiment
thanks :) +rep
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Offline aquarian93

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Re: CHEMISTRY PAPER 1 HERE
« Reply #174 on: June 11, 2009, 03:26:55 pm »
ugh the karma isnt leting me rep u, sry :(
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Offline girl_92

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Re: CHEMISTRY PAPER 1 HERE
« Reply #175 on: June 11, 2009, 03:27:09 pm »
Quote from: aquarian93 on June 11, 2009, 03:23:29 pm
guys i need help wid May 06, no. 29
y is it D? doesnt chrome plated keyring, rust?
ya chromium is resistant to corrosion n the brass scre will not rust because thte test tube contains nitrogen
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some people sleep to dream while othrs wakeup to follow dem im the second type how abt u

Offline aquarian93

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Re: CHEMISTRY PAPER 1 HERE
« Reply #176 on: June 11, 2009, 03:28:00 pm »
the OH in the COOH of a carboxilyic acid reacts wid NaOH?
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Re: CHEMISTRY PAPER 1 HERE
« Reply #177 on: June 11, 2009, 03:32:57 pm »
Quote from: aquarian93 on June 11, 2009, 03:28:00 pm
the OH in the COOH of a carboxilyic acid reacts wid NaOH?
Yes, it does! :)
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Offline girl_92

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Re: CHEMISTRY PAPER 1 HERE
« Reply #178 on: June 11, 2009, 03:33:14 pm »
Quote from: aquarian93 on June 11, 2009, 03:28:00 pm
the OH in the COOH of a carboxilyic acid reacts wid NaOH?
wht r u tryin to say i culdnt get u
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some people sleep to dream while othrs wakeup to follow dem im the second type how abt u

Offline aquarian93

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Re: CHEMISTRY PAPER 1 HERE
« Reply #179 on: June 11, 2009, 03:34:55 pm »
Quote from: madee on June 11, 2009, 03:33:14 pm
Quote from: aquarian93 on June 11, 2009, 03:28:00 pm
the OH in the COOH of a carboxilyic acid reacts wid NaOH?
wht r u tryin to say i culdnt get u

its a question from may 06 paper
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