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Chemistry: Post your doubts here!

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hello there.
Can anybody answer this:
A solution of vanadium (V) ions in 1 mol dm-3 H2SO4 slowly oxidises arsenic (III) oxide to arsenic (V) oxide according to the following (unbalanced) equation. Balance the equation. :cry:
As2O3 + VO2^+ + H+ ---> As2O5 + VO2+ + H2O
 
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People please help me here i dont get this one question from paper 2 seems quite simple:unsure:

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_s03_qp_2.pdf
http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Chemistry (9701)/9701_s03_ms_1 2 3 4 5 6.pdf
Q1 part C it says explain your answer. but i dont get the answer they gave in the mark scheme Why does the ratio have to be 3:1?
If you have a look at the relative abundances, that is,
H35Cl (line at m/e value 36) has relative abundance 90
H37Cl (line at m/e value 38 has relative abundance 30
Hence these show that 35Cl and 37Cl are in the ratio 3:1 :)
 
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If you have a look at the relative abundances, that is,
H35Cl (line at m/e value 36) has relative abundance 90
H37Cl (line at m/e value 38 has relative abundance 30
Hence these show thet 35Cl and 37Cl are in the ratio 3:1 :)

well i get that part but how does that help in telling us that these are the peaks that will determine the proportions of the isotopes of chlorine
like how does the ratio 3:1 tell us that?
 
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well i get that part but how does that help in telling us that these are the peaks that will determine the proportions of the isotopes of chlorine
like how does the ratio 3:1 tell us that?
I'm sorry i don't get what u r trying to say.
 
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hello there.
Can anybody answer this:
A solution of vanadium (V) ions in 1 mol dm-3 H2SO4 slowly oxidises arsenic (III) oxide to arsenic (V) oxide according to the following (unbalanced) equation. Balance the equation. :cry:
As2O3 + VO2+ + H+ ---> As2O5 + VO2+ + H2O

Are you sure this equation is correct because i think the oxidation state of VO2+ will change as it oxidizes the As2O3 and so will be reduced itself?
 
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Are you sure this equation is correct because i think the oxidation state of VO2+ will change as it oxidizes the As2O3 and so will be reduced itself?
Sorry while typing there's been some problem
on the reactants side the VO2^+ (the plus is superscript)
 
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well i get that part but how does that help in telling us that these are the peaks that will determine the proportions of the isotopes of chlorine
like how does the ratio 3:1 tell us that?
Oh now i get it. it simply asks u how you arrived at 3:1. The explanation lies in the abundances.
 
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Oh now i get it. it simply asks u how you arrived at 3:1. The explanation lies in the abundances.

Oh ok rite i read the question again and before i was reading it wrong or taking it in another sense but i get it now so first we'r supposed to come to the 3:1 ratio and then explain how we got it which is basically by taking in consideration the relative abundances. well thanks u put me on the rite track.
 
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Oh ok rite i read the question again and before i was reading it wrong or taking it in another sense but i get it now so first we'r supposed to come to the 3:1 ratio and then explain how we got it which is basically by taking in consideration the relative abundances. well thanks u put me on the rite track.
u're most welcomed ^^
 
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Can anybody answer this question please??? :cry: :cry:
 

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can somebody please help me to work out the question on planning??
i'm finding it a real pain.
please help me!
pg 6 ex 2
 

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Guys, I think the marking scheme is wrong here. Check out Question 5.

The third box, the marking key says E only.
But wouldn't the ketone and aldeyde be reduced by H2(Hydrogen)
It should've been C,D and E.
 

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