Author Topic: CHEMISTRY PAPER 1 HERE  (Read 38752 times)

Offline sweetsh

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Re: CHEMISTRY PAPER 1 HERE
« Reply #300 on: June 11, 2009, 08:20:48 pm »
No its okay

Offline GodOfWar

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Re: CHEMISTRY PAPER 1 HERE
« Reply #301 on: June 11, 2009, 08:52:20 pm »
um sweetsh.. do u EVER go offline
You got me ten feet off the ground <|3

Offline sweetsh

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Re: CHEMISTRY PAPER 1 HERE
« Reply #302 on: June 11, 2009, 08:53:25 pm »
Yes..
Actually if you wonder I keep my PC open during the day and check the forum from time to time..Just to make sure everything is going on in the proper way

Offline goin4dakill

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Re: CHEMISTRY PAPER 1 HERE
« Reply #303 on: June 11, 2009, 08:56:40 pm »
Isnt a redox reactions when the reaction has oxidation and reduction at the same time???

The how come S + 2O2--> SO4 is a redox reaction???


Offline GodOfWar

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Re: CHEMISTRY PAPER 1 HERE
« Reply #304 on: June 11, 2009, 09:05:03 pm »
oh, ur the admin  ;D  heheh
You got me ten feet off the ground <|3

Offline bball92

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Re: CHEMISTRY PAPER 1 HERE
« Reply #305 on: June 11, 2009, 09:09:38 pm »
Isnt a redox reactions when the reaction has oxidation and reduction at the same time???

The how come S + 2O2--> SO4 is a redox reaction???



It isnt... :P

Offline sweetest angel

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Re: CHEMISTRY PAPER 1 HERE
« Reply #306 on: June 11, 2009, 09:14:14 pm »
Isnt a redox reactions when the reaction has oxidation and reduction at the same time???

The how come S + 2O2--> SO4 is a redox reaction???


well i finally understood it
u see the oxidation is easy to get since sulphur gains oxygen atom
now reduction: the oxidation is where the oxygen here becomes from an atom of no oxidation state to losing being of oxidation state of -2 in SO4, thus lose of oxidation state is reduction . that's it ;D!
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Offline Hope

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Re: CHEMISTRY PAPER 1 HERE
« Reply #307 on: June 11, 2009, 09:15:08 pm »
Could anyone please explain why the answer to November 2008 qn 23 is A?

Offline sweetest angel

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Re: CHEMISTRY PAPER 1 HERE
« Reply #308 on: June 11, 2009, 09:18:51 pm »
OK June 2005.

Which reacts with cold water only when finely powdered?
A. Calcium
B. Copper
C. Sodium
D. Magnesium

I put Sodium because its higher in the reactivity series, but the ms said magnesium...
WHY?? help urgently..?
well its in the chapter "PERIODIC TABLE"..where one of the things u gotta learn is that from group II elements magnesium and beryllium react only with steam...and with cold water if powdered, to produce their oxide and liberate hydrogen..while as u knw otha elements of group II react with cold water to form their hydroxide and liberate hydrogen gas
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Offline cockyxrocker

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Re: CHEMISTRY PAPER 1 HERE
« Reply #309 on: June 11, 2009, 09:19:18 pm »
Nov 2008 questions 15,20,29
help!..

Offline sweetest angel

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Re: CHEMISTRY PAPER 1 HERE
« Reply #310 on: June 11, 2009, 09:20:56 pm »
Could anyone please explain why the answer to November 2008 qn 23 is A?
magnesium chloride is ALREADY a salt..thus won't react with anything let it be an acid or not to form anotha salt...thus A where that option has a cross!
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Offline sweetsh

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Re: CHEMISTRY PAPER 1 HERE
« Reply #311 on: June 11, 2009, 09:21:28 pm »
15)a
20)b
29)b

Offline Hope

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Re: CHEMISTRY PAPER 1 HERE
« Reply #312 on: June 11, 2009, 09:24:20 pm »
I thought about it..and thought so. But, I did a bit of research and found that it could react! That's just too confusing :(

Offline sweetest angel

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Re: CHEMISTRY PAPER 1 HERE
« Reply #313 on: June 11, 2009, 09:30:54 pm »
Nov 2008 questions 15,20,29
help!..
15) C...if it absorbs 10 from 1000cm^3 then it would absorb twice as much of heat from 500cm^3 since volume is halved!
20)HCL + BaNO3-->HNO3+BACL ....therefore the acidic nitric acid decrease the pH and since barium reacts with chlorine,therfore no precipitate
29)metals donot have 6 in their outa shell and always form ionic compounds thus B
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Offline sweetsh

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Re: CHEMISTRY PAPER 1 HERE
« Reply #314 on: June 11, 2009, 09:35:15 pm »
I can't get this, what's the difference between molten and aqueos?