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what do you mean by only two papers are same?Only two papers in every Oct/Nov session only are same. Otherwise, every other paper is different.
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what do you mean by only two papers are same?Only two papers in every Oct/Nov session only are same. Otherwise, every other paper is different.
There are 3 variants of Chemistry papers. Out of those 3, 2 are same in every Oct/Nov session.what do you mean by only two papers are same?
oh really? I didn't know that, thanxThere are 3 variants of Chemistry papers. Out of those 3, 2 are same in every Oct/Nov session.
E cell is always positive thoughIf E cell is positive then the reaction will be proceeding in forward direction. This means more products will be formed.
J is formed by replacing H from the tertiary carbon in the middle. This happens at rate=21.Help part b ivView attachment 60404
Not always...E cell is always positive though
I realised.Not always...
wait i dont get how E cell can be negative LOLNot always...
June 13 P41, 1) c) ii)
mark scheme ays its forward (more product) because E is more than 0 (its positive)
but isnt that always the case ?? Even if both half cells is negative its going to be (-0.12)-(-0.67)= positive??
so why are there more products?
wait i dont get how E cell can be negative LOL
How can E cell be negative?
Ecell will be positive for reactions which are feasible/spontaneous in the forward direction. If Ecell is negative then the reaction is feasible only for the backward direction.I realised.
Can you explain why having a positive E cell mean there are more products?
I realised.
Can you explain why having a positive E cell mean there are more products?
wait i dont get how E cell can be negative LOL
How can E cell be negative?
As TariqBhai explained, if Ecell value is positive means reaction will be occurring. As reaction is occurring that simply means reaction is moving in forward direction. This means more product. And the reaction which arent feasible are the ones that have negative Ecell and the reaction will move backwards.Ecell will be positive for reactions which are feasible/spontaneous in the forward direction. If Ecell is negative then the reaction is feasible only for the backward direction.
Since you calculated that Ecell was positive then the reaction:
2Fe + 2I <=> 2Fe+ I 2
Will only occur in the forward direction: 2Fe + 2I => 2Fe+ I 2
If Ecell was negative then the reaction would only occur in backward direction: 2Fe+ I 2 => 2Fe + 2I
MS is talking about Ecell and not E.
I couldnt find any ms. But here is what u can get idea similar to ms. http://papers.gceguide.com/A Levels/Chemistry (9701)/9701_w15_er.pdfocto nov 2015 mark scheme 21??????
http://papers.gceguide.com/A Levels/Chemistry (9701)/9701_w15_ms_21.pdfocto nov 2015 mark scheme 21??????
didnt got it.. THanks thoough
You are given this situation:
This was a simple question, let's do a bit tricky question now Consider the question below:
This was a simple question, let's do a bit tricky question now Consider the question below:
You know that the number of moles of Nitrogen, N2, at equilibrium are 2.32mol which are 0.32 moles greater than the number of moles initially. This tells us that, some amount of NH3 has broken down to give this increase in mole of N2 at equilibrium. So by using the mole ratios, find the number of moles of NH3 which have decomposed to give 0.32 mole of N2.
n(N2) : n(NH3) = 1 : 2
^ they are in this ratio, so the moles of NH3 broken are:
0.32 * 2 = 0.64mol
Subtract ^ this amount of mole from the initial number of moles NH3, to find the number of NH3 at equilibrium. 2.40-0.64 = 1.76mol
Now in a similar way, find the number of moles of H2 formed by the decomposition of NH3.
n(H2) : n(NH3) = 3 : 2
so moles of H2 formed = 0.64 * 3/2 = 0.96mol <----- add this amount to the initial number of moles of H2, to find the the no. of moles of H2 at equilibrium: 6 + 0.96 = 6.96mol
Now you have this information:
View attachment 60509
Since the volume is 1dm^3, the conc. of the substances at equilibrium will be equal to the moles of the substances.
Finally use the Kc expression, to get your final answer:
So the answer is A.
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