Pure aluminium is soft. Aircraft bodies are made from aluminium alloys.
.1
Explain why pure aluminium is soft.
[2 marks].2
Explain why aluminium alloys are harder than pure aluminium.
[2 marks]AQA GCSE Chemistry June 2023 Paper 2F
5 questions on this paper's topics
18:001 of 5
Burning fuels can release several pollutants.
.1
Which pollutant is a toxic gas that reduces the blood's ability to carry oxygen?
[1 mark].2
Which pollutant causes global dimming?
[1 mark].3
Name the environmental problem caused by sulfur dioxide dissolving in rain water.
[1 mark]Chemical reactions can transfer energy to or from the surroundings.
.1
Which two reactions are exothermic? Tick two boxes.
[2 marks].2
Give one everyday use of an endothermic reaction.
[1 mark]A student tests two samples of a white solid. The pure solid melts at 122 °C.
Sample A melts at 122 °C. Sample B melts between 115 °C and 119 °C.
.1
Which sample is impure?
[1 mark].2
Give the meaning of a pure substance in chemistry.
[1 mark].3
Which of these is a formulation?
[1 mark]A student adds marble chips to hydrochloric acid and collects the carbon dioxide in a gas syringe.
| Time in s | 0 | 10 | 20 | 30 | 40 | 50 | 60 |
|---|---|---|---|---|---|---|---|
| Volume in cm³ | 0 | 22 | 38 | 50 | 56 | 60 | 60 |
.1
Calculate the mean rate of reaction in the first 30 seconds.
[2 marks].2
Give the earliest time in the table by which the reaction had stopped.
[1 mark].3
Describe how the rate changes during the reaction.
[1 mark]