Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Chapter
States of Matter
102 practice questions
Topics covered
Practice questions
61–70 of 102
Question 61
2 marks · Easy
Answer and see the solution →Explain why it is important to heat the evaporating basin until its mass remains constant when measuring the solubility of a salt.
Question 62
1 mark · Easy
Answer and see the solution →State what is meant by a solution in chemistry.
Question 63
3 marks · Easy
Answer and see the solution →(a)The diagram below shows a solubility curve for a salt.
Solubility curve for salt W. (i)[1 mark]State the solubility of salt W at 20°C.
(ii)[1 mark]Describe what happens to the solubility of salt W as the temperature increases from 0°C to 60°C.
(iii)[1 mark]Explain, with reference to the solubility curve, how to tell when a solution of salt W at 40°C is saturated.
Question 64
2 marks · Easy
Answer and see the solution →A student found that 25.8 g of sodium chloride was obtained after evaporating all the water from a saturated solution made with 75 g of water at a certain temperature.
Calculate the solubility of sodium chloride in g per 100 g water at that temperature. Show your working.
Question 65
2 marks · Normal
Answer and see the solution →State the meaning of the following terms as used in chemistry:
(a)[1 mark]solute
(b)[1 mark]solvent
Question 66
4 marks · Normal
Answer and see the solution →The graph below shows the solubility of two different salts (potassium nitrate and sodium chloride) in water as the temperature increases.
(a)[1 mark]Using the graph, estimate the solubility of potassium nitrate in water at 30°C.
(b)[1 mark]State which salt is more soluble at 0°C. Justify your answer using data from the graph.
(c)[2 marks]Explain what is meant by a 'solubility curve'.
Question 67
3 marks · Normal
Answer and see the solution →A student wants to find the solubility of copper(II) sulfate in water at 30°C. She carries out the following experiment:
1. Weighs an empty evaporating basin: 28.60 g 2. Adds a known mass of saturated copper(II) sulfate solution at 30°C to the basin: total mass 62.10 g 3. Evaporates all the water. The mass of evaporating basin plus copper(II) sulfate crystals after heating is 36.10 g
Calculate the solubility of copper(II) sulfate in water at 30°C in g per 100 g water, giving your answer to 2 significant figures.
Question 68
1 mark · Normal
Answer and check →Which precaution should be taken to ensure an accurate measurement of solubility during the experiment to find the solubility of a salt in water?
- A.Use cold tap water to dissolve the salt
- B.Pour undissolved solid into the evaporating basin with the solution
- C.Weigh the evaporating basin before and after adding the solution
- D.Include some dry solid in the final weighing
Question 69
2 marks · Normal
Answer and see the solution →State the meaning of the following:
(a)[1 mark]solution
(b)[1 mark]saturated solution
Question 70
4 marks · Normal
Answer and see the solution →The graph below shows the solubility curves of two substances, ammonium chloride and sodium chloride, in water.
(a)[2 marks]Compare how the solubility of ammonium chloride and sodium chloride changes as temperature increases.
(b)[1 mark]Estimate the solubility of ammonium chloride at 50°C using the graph.
(c)[1 mark]Which substance is more soluble at 0°C?