Key Stage 3 Science Book 1 Assessments
Mixing, Dissolving and Separating (Purple level)
1. Forensic scientists collect fingerprints from crime scenes. Describe the technique they use on the
fingerprints to find out information about them. [4 marks]
2. Compare and contrast the two processes: mining rock salt and solution mining. [4 marks]
3. If 4 grams of salt is dissolved in 79 grams of water, what is the total mass of the final solution? [1
mark]
a) 83 g
b) 4 g
c) 79 g
d) 81 g
4. Define the term solubility. [2 marks]
5. A solute is added to a solvent to make a mixture. How does the mass of the mixture compare with the
mass of the solute and solvent before they were mixed? [1 mark]
a) The mass of the mixture is less than the mass of the solute
b) The mass of the mixture is greater than the mass of the solute and solvent
c) The mass of the mixture is equal to the mass of the solute and solvent
d) The mass of the mixture is less than the mass of the solute and solvent
© HarperCollinsPublishers 2014
Key Stage 3 Science Book 1 Assessments
6. Match the description to the picture. [3 marks]
An element
Two elements
A compound
Mixture of two compounds
Mixture of an element and a
compound
7. Why is alcohol used in the making of perfume? [2 marks]
8. Which two processes are involved in distillation? [2 marks]
a) Melting
b) Freezing
c) Filtering
d) Condensing
e) Evaporating
9. How can distillation be used to increase the strength of a solution? [2 marks]
© HarperCollinsPublishers 2014
Key Stage 3 Science Book 1 Assessments
10. The graph shows the solubility of oxygen in water. What does the graph tell you? [2 marks]
11. Leroy used chromatography to investigate the food colourings used in some of his favourite sweets.
Here’s a black and white diagram of the chromatogram, which shows his results.
Use the information to complete the following sentence using a number between 1 and 9. Sweet F
contains at
least
food colourings [1 mark]
© HarperCollinsPublishers 2014
Key Stage 3 Science Book 1 Assessments
12. Priya and Leo added soap solution to four water samples, A, B, C and D. They shook the mixtures and
recorded the time taken for the lather to disappear. The results are shown in this table:
What do these results tell Priya and Leo about the water samples? Explain your answer. [2 marks]
13. How can you tell when a solution has become saturated? [1 mark]
a) The solute all dissolves
b) Bubbles can be seen
c) Some solvent can be seen in the solution
d) Some solute can be seen in the solution
14. What apparatus would you use to separate a mixture of immiscible substances? [1 mark]
a) Liebig condenser
b) Sieve
c) Separating funnel
d) Chromatography paper
15. Choose from the list below to complete this sentence: Cryogenic distillation operates at __ [1 mark]
a) low temperature and high pressure
b) high temperature and low pressure
c) high temperature and high pressure
d) low temperature and low pressure
© HarperCollinsPublishers 2014
Key Stage 3 Science Book 1 Assessments
16. Ben and Lucy investigated how much copper sulfate would dissolve in 100 cm3 of water at different
temperatures. This is a graph of their results.
What is the solubility of copper sulfate in 100 cm3 of water at 75 OC? [1 mark]
a) 45 g
b) 50 g
c) 55 g
d) 60 g
© HarperCollinsPublishers 2014