1.
State what is meant by a homologous series.
[1 mark]
- same functional group, differ by CH₂
JD SCIENCE
Organic chemistry core
Indicative marking points. Award marks for equivalent scientific or mathematical wording. Do not issue this sheet with the student worksheet.
2.
State what is meant by isomerism.
[1 mark]
- same molecular formula, different structure
3.
State what is meant by a nucleophile.
[1 mark]
- electron-pair donor
4.
State what is meant by an electrophile.
[1 mark]
- electron-pair acceptor
5.
State what is meant by free-radical substitution.
[1 mark]
- alkanes + halogens in UV
6.
State what is meant by electrophilic addition.
[1 mark]
- alkenes + Br₂ / HBr
7.
State what is meant by nucleophilic substitution.
[1 mark]
- haloalkanes + OH⁻
8.
State what is meant by oxidation of alcohols.
[1 mark]
- primary → aldehyde → carboxylic acid; secondary → ketone
9.
State what is meant by a carbonyl test.
[1 mark]
- Brady's / 2,4-DNP orange ppt
10.
State what is meant by optical isomerism.
[1 mark]
- chiral carbon, four different groups
11.
Devon is asked about a homologous series in a Edexcel Chemistry paper.
(a) [2 marks]
- gradual change in physical properties
(b) [3 marks]
- same general formula
12.
Devon is asked about isomerism in a Edexcel Chemistry paper.
(a) [2 marks]
- structural and stereoisomerism
(b) [3 marks]
- E–Z and optical
13.
Devon is asked about a nucleophile in a Edexcel Chemistry paper.
(a) [2 marks]
- OH⁻, CN⁻, NH₃
(b) [3 marks]
- attacks δ+ carbon
14.
Devon is asked about an electrophile in a Edexcel Chemistry paper.
(a) [2 marks]
- H⁺, Br⁺ (from Br₂/FeBr₃), NO₂⁺
(b) [3 marks]
- attacks electron-rich centres
15.
Devon is asked about free-radical substitution in a Edexcel Chemistry paper.
(a) [2 marks]
- initiation, propagation, termination
(b) [3 marks]
- mixture of products
16.
Devon is asked about electrophilic addition in a Edexcel Chemistry paper.
(a) [2 marks]
- carbocation intermediate
(b) [3 marks]
- Markownikoff
17.
Molecular formula of hexane
[3 marks]
- Final answer: C₆H₁₄
18.
How many structural isomers of C₄H₁₀
[3 marks]
- Final answer: 2
19.
Mr of CH₃COOH
[3 marks]
- Final answer: 60
20.
Moles in 6.0 g of ethanoic acid
[3 marks]
- Final answer: 0.10 mol
21.
A chiral carbon is in CH₃CHBrCH₂CH₃. How many optical isomers
[3 marks]
- Final answer: 2
22.
Percentage yield 7.2 g from theoretical 9.0 g
[3 marks]
- Final answer: 80%
23.
Devon carries out a Edexcel-style required practical linked to organic chemistry. This is a typical Edexcel required-practical style question.
(a) [2 marks]
- Independent: the independent variable for this topic
- Dependent: the measured outcome
(b) [2 marks]
- keep all other variables constant
- so the test is fair / only one variable is changed
(c) [2 marks]
- repeat and calculate a mean / use a tighter method
24.
Devon carries out collecting valid data for organic chemistry. This is a typical Edexcel required-practical style question.
(a) [2 marks]
- Independent: a chosen factor
- Dependent: a quantitative measurement
(b) [2 marks]
- calibrated instrument
- so the test is fair / only one variable is changed
(c) [2 marks]
- systematic error from zero error
25.
Devon carries out drawing a graph for organic chemistry. This is a typical Edexcel required-practical style question.
(a) [2 marks]
- Independent: x-variable
- Dependent: y-variable
(b) [2 marks]
- same scale / same apparatus
- so the test is fair / only one variable is changed
(c) [2 marks]
- not drawing a line of best fit through the trend
26.
Devon carries out evaluating a method about organic chemistry. This is a typical Edexcel required-practical style question.
(a) [2 marks]
- Independent: method change
- Dependent: precision / accuracy
(b) [2 marks]
- same sample size
- so the test is fair / only one variable is changed
(c) [2 marks]
- too few repeats
27.
Compare a homologous series with isomerism.
[4 marks]
- same functional group, differ by CH₂
- same molecular formula, different structure
- give one linked difference
28.
Compare isomerism with a nucleophile.
[4 marks]
- same molecular formula, different structure
- electron-pair donor
- give one linked difference
29.
Compare a nucleophile with an electrophile.
[4 marks]
- electron-pair donor
- electron-pair acceptor
- give one linked difference
30.
Compare an electrophile with free-radical substitution.
[4 marks]
- electron-pair acceptor
- alkanes + halogens in UV
- give one linked difference
31.
Apply your knowledge of nucleophilic substitution to this situation: Sn1 or Sn2
[3 marks]
- Sn1 or Sn2
32.
Apply your knowledge of oxidation of alcohols to this situation: acidified dichromate
[3 marks]
- acidified dichromate