Chromatography
12.3What the syllabus asks of you
- Describe how paper chromatography is used to separate mixtures of soluble substances, using a suitable solvent
- Describe the use of locating agents when separating mixtures containing colourless substances. Knowledge of specific locating agents is not required
- Interpret simple chromatograms to identify: (a) unknown substances by comparison with known substances (b) pure and impure substances
- State and use the equation for Rf: Rf = distance travelled by substance / distance travelled by solvent
Read the notes first
Chapter 12: Chromatography
Drill this topic
Every question on Chromatography, untimed, marked as you go.
Make a worksheet
Choose the years and how many questions, then print it with the answers on separate pages.
20 questions
1May / June 2026 · Paper 11 · Q39Show mark scheme →
AA dye can have an Rf value of 1.2.
BA dye can have different Rf values with different solvents.
CAll blue dyes have the same Rf value.
DChromatography can only be used for coloured substances such as dyes.
Mark scheme
2May / June 2026 · Paper 12 · Q38Show mark scheme →
Acitric acid, malic acid and lactic acid
Bcitric acid, malic acid and succinic acid
Cmalic acid, lactic acid and succinic acid
Dtartaric acid, citric acid and malic acid
Mark scheme
3Oct / Nov 2025 · Paper 11 · Q38Show mark scheme →
AR is completely insoluble in the solvent used.
BThe Rf value of Q is greater than the Rf value of S.
CX is a mixture of Q, R and S.
DThe paper is placed in the solvent with the solvent above the baseline.
Mark scheme
4Oct / Nov 2025 · Paper 12 · Q38Show mark scheme →
Achromatography
Bcrystallisation
Cdistillation
Dfiltration
Mark scheme
5May / June 2025 · Paper 12 · Q37Show mark scheme →
AP, Q and R
BP, Q and another substance
CP and Q only
DP and R only
Mark scheme
6Oct / Nov 2024 · Paper 11 · Q39Show mark scheme →
AMeasure the Rf values of the spots carefully.
BRun the chromatogram for a longer time.
CRun the chromatogram using a different solvent.
DUse a locating agent.
Mark scheme
7May / June 2024 · Paper 11 · Q39Show mark scheme →
A0.22
B0.25
C0.33
D0.43
Mark scheme
8Oct / Nov 2023 · Paper 12 · Q39Show mark scheme →
AA
BB
CC
DD
Mark scheme
9May / June 2023 · Paper 11 · Q39Show mark scheme →
Agap 1: $\frac{x}{y}$, gap 2: red-brown
Bgap 1: $\frac{x}{y}$, gap 2: green
Cgap 1: $\frac{y}{x}$, gap 2: red-brown
Dgap 1: $\frac{y}{x}$, gap 2: green
Mark scheme
10May / June 2023 · Paper 12 · Q39Show mark scheme →
Alarger Rf value: X; requires a locating agent: X
Blarger Rf value: X; requires a locating agent: Y
Clarger Rf value: Y; requires a locating agent: X
Dlarger Rf value: Y; requires a locating agent: Y
Mark scheme
11Oct / Nov 2021 · Paper 11 · Q4Show mark scheme →
AMeasure the Rf values of the spots carefully.
BRun the chromatogram for a longer time.
CRun the chromatogram using a different solvent.
DUse a locating agent.
Mark scheme
12Oct / Nov 2020 · Paper 11 · Q3Show mark scheme →
A
B
C
D
Mark scheme
13Oct / Nov 2020 · Paper 12 · Q3Show mark scheme →
AA dye with an Rf value of 1.2 can be present in a mixture.
BA dye could have a different Rf value if a different solvent was used.
CAll blue dyes have the same Rf value.
DChromatography can only be used for coloured substances such as dyes.
Mark scheme
14May / June 2020 · Paper 12 · Q3Also set in May / June 2020 Paper 11, Oct / Nov 2016 Paper 11Show mark scheme →
A$\dfrac{x}{y}$ red-brown
B$\dfrac{x}{y}$ green
C$\dfrac{y}{x}$ red-brown
D$\dfrac{y}{x}$ green
Mark scheme
15May / June 2019 · Paper 11 · Q3Show mark scheme →
Achromatography paper, locating agent, marker pen, solvent
Bchromatography paper, locating agent, pencil, ruler, solvent
Cchromatography paper, locating agent, ruler, solvent, thermometer
Dchromatography paper, locating agent, pencil, solvent, thermometer
Mark scheme
16May / June 2019 · Paper 12 · Q3Show mark scheme →
Acitric acid, malic acid and lactic acid
Bcitric acid, malic acid and succinic acid
Cmalic acid, lactic acid and succinic acid
Dtartaric acid, citric acid and malic acid
Mark scheme
17Oct / Nov 2018 · Paper 11 · Q2Show mark scheme →
Alarger Rf value: X; requires a locating agent: X
Blarger Rf value: X; requires a locating agent: Y
Clarger Rf value: Y; requires a locating agent: X
Dlarger Rf value: Y; requires a locating agent: Y
Mark scheme
18Oct / Nov 2017 · Paper 12 · Q5Show mark scheme →
AThis causes the spot nearest the bottom of the paper to catch up with the spot above it.
BThis makes it impossible to calculate Rf values.
CThis makes it impossible to use a locating agent.
DThis results in a safety hazard caused by solvent fumes.
Mark scheme
19May / June 2017 · Paper 12 · Q6Show mark scheme →
ASample 2 has travelled the furthest and sample 3 is pure compound Q.
BSample 3 has travelled the furthest and sample 2 is pure compound Q.
CSample 4 has travelled the furthest and sample 1 is pure compound Q.
DSample 4 has travelled the furthest and sample 2 is pure compound Q.
Mark scheme
20May / June 2016 · Paper 12 · Q3Show mark scheme →
AA
BB
CC
DD
Mark scheme