AQA GCSE Combined Science November 2021 Chemistry Paper 2F: timed practice

6 marksFoundation and Higher5.7.1.2 Fractional distillation and petrochemicals5.7.1.3 Properties of hydrocarbons

Spec and skills

Crude oil is separated into fractions in a fractionating column.

Explain how fractional distillation separates crude oil into fractions.

[6 marks]

6 marksFoundation and HigherRequired practical 135.10.1.2 Potable water

Spec and skills

A student has samples of tap water, sea water and rain water.

Plan an investigation to compare the pH and the mass of dissolved solids in the three samples, and to purify the sea water by distillation.

[6 marks]

4 marksFoundation and Higher5.9.3.1 Atmospheric pollutants from fuels5.9.3.2 Properties and effects of atmospheric pollutants

Spec and skills

A faulty gas heater burns methane in a limited supply of air.

.1

Which two substances could form from incomplete combustion but not from complete combustion? Tick two boxes.

[2 marks]

.2

Explain why carbon monoxide from a faulty heater is dangerous.

[2 marks]

6 marksFoundation and Higher5.10.2.1 Life cycle assessment

Spec and skills

The table shows data from a life cycle assessment of two shopping bags, each used once.

Table: the plastic bag uses 0.6 megajoules and 1.2 grams of raw material from crude oil, releases 0.12 kilograms of carbon dioxide, and lasts a very long time in landfill; the paper bag uses 1.5 megajoules and 50 grams of raw material from trees, releases 0.34 kilograms of carbon dioxide, and biodegrades in weeks.
Measure	Plastic bag	Paper bag
Energy used in MJ	0.6	1.5
Raw material	Crude oil (finite)	Trees (renewable)
Carbon dioxide released in kg	0.12	0.34
After disposal	Lasts many years in landfill	Biodegrades in weeks

Evaluate the environmental impact of the two bags. Use the data in the table.

[6 marks]

6 marksFoundation and HigherRequired practical 115.6.1.2 Factors which affect the rates of chemical reactions

Spec and skills

A student investigates how the concentration of hydrochloric acid affects the rate of its reaction with magnesium ribbon. Hydrogen gas is produced.

Plan an investigation using a gas collection method. Include the variables the student should control.

[6 marks]