Edexcel Chemistry A2 Unit 5 ~ Wednesday 19th June 2013 (Now Closed)

Ah the elusive question 16. I'm starting to doubt whether it even exists.

Ah the elusive question 16. I'm starting to doubt whether it even exists.

it was talking about planar molecules,

Which one of these isnt planar?

A: C6H6, (Benzene ring)

B: CCL4

C: BF3

D: Pt(NH3)2(CL)2

I chose CCL4, as its tetrahedral and all the others are planar


I think the grade boundaries for this exam will be minimum 70 for an A, This paper was relatively easy considering the vast amount of stuff they could have asked, everything was straightforward.

Multiple Choice (Unofficial) Mark Scheme

Explanation of question/answer in brackets

1 - C (1.3 - 0.4 as moles independent of E cell)
2 - D (Delta S total is proportional to E cell)
3 - A Can't remember which letter (changing conc of Mn2+ would alter E cell of the half equation)
4 - C (Fe2+ acts as a catalyst)
5 - C (EDTA leads to an increase in Entropy therefore more stable)
6 - C (equilibrium shifts to the right)
7 - A (CO2 would lower pH as it provides the H+)
8 - D (Cr was in ox states +3, +6, +2)
9 - D (hetero catalysts don't change oxidation state)
10 - D (ligand exchange when ammonia reacts with given complex)
11 - A (tertiary alcohol (CH3)2-C(OH)-CH3 will not be oxidised by dichromate)
12 - B (3 isomers of dibromobenzene)
13 - B (COO- and NH2 groups on the amino acid as it was in basic solution)
14 - D (COCl and NH2 groups to form the polyamide)
15 - B (had chiral centre but had only one COOH and NH2 group so was neutral)
16 - ??
17 - B (C3H8 from simple mole ratios)
18 - A (oxygen accepts pair of electrons in reduction mechanism of carbonyl)
19 - B (C-O bond broken in the acid as this was the only one which could be deduced from the question)
20 - C (CH2=CH2 requires electrophilic action whilst H- is a nucleophile)

All credit goes to marjunior for uploading the questions

Anyone remember question 16?

hi, is this all confirmed and agreed?

Yeah, I think everyone is in agreement with this.

Multiple Choice (Unofficial) Mark Scheme - FINAL

Explanation of question/answer in brackets

1 - C (1.3 - 0.4 as moles independent of E cell)
2 - D (Delta S total is proportional to E cell)
3 - A Can't remember which letter (changing conc of Mn2+ would alter E cell of the half equation)
4 - C (Fe2+ acts as a catalyst)
5 - C (EDTA leads to an increase in Entropy therefore more stable)
6 - C (equilibrium shifts to the right)
7 - A (CO2 would lower pH as it provides the H+)
8 - D (Cr was in ox states +3, +6, +2)
9 - D (hetero catalysts don't change oxidation state)
10 - D (ligand exchange when ammonia reacts with given complex)
11 - A (tertiary alcohol (CH3)2-C(OH)-CH3 will not be oxidised by dichromate)
12 - B (3 isomers of dibromobenzene)
13 - B (COO- and NH2 groups on the amino acid as it was in basic solution)
14 - D (COCl and NH2 groups to form the polyamide)
15 - B (had chiral centre but had only one COOH and NH2 group so was neutral)
16 - B (CCl4 is tetrahedral Cisplatin, Benzene and BF3 were all planar)
17 - B (C3H8 from simple mole ratios)
18 - A (oxygen accepts pair of electrons in reduction mechanism of carbonyl)
19 - B (C-O bond broken in the acid as this was the only one which could be deduced from the question)
20 - C (CH2=CH2 requires electrophilic action whilst H- is a nucleophile)

All credit goes to marjunior for uploading the questions

I would have thought that 18 is C

How comes it's A?

The mark scheme is out for this paper, but only for teachers, guys. Anyone have access to it, or can post it up??? Thanks.

It's too late to change anything now ... Reading the ms won't change anything so you might as well wait a couple days until results

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So, any changes to grade boundary predictions now that the markscheme is out?