Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Chapter
States of Matter
102 practice questions
Topics covered
Practice questions
31–40 of 44 · Normal
Question 31
3 marks · Normal
Answer and see the solution →The following terms are commonly used in describing solutions:
(a)Define the following terms:
(i) solvent
(ii) solute
(iii) saturated solution
(i)[1 mark]solvent
(ii)[1 mark]solute
(iii)[1 mark]saturated solution
Question 32
4 marks · Normal
Answer and see the solution →The table below shows the solubility of two salts in water at different temperatures.
Solubility data for Salt X and Salt Y in water Temperature (°C) Solubility of Salt X (g/100g water) Solubility of Salt Y (g/100g water) 20 32 13 40 44 19 60 56 25 80 68 31 (a)[4 marks]On the axes below, plot the solubility curves for Salt X and Salt Y using the data from the table.
Use a suitable scale and label both curves clearly.
Question 33
2 marks · Normal
Answer and see the solution →A student mixes 8.0 g of a salt with 40.0 g of water at 30°C. After stirring, some solid remains undissolved. Use the solubility equation to calculate the solubility (in g per 100 g water) of the salt at 30°C for this experiment.
Question 34
4 marks · Normal
Answer and see the solution →The table below shows the solubility of lithium nitrate at different temperatures.
Solubility of lithium nitrate at various temperatures Temperature /°C Solubility /g per 100 g water 10 46.0 30 62.0 50 78.5 70 94.0 90 110.0 (a)[2 marks]Plot a solubility curve for lithium nitrate using the data in the table. Label both axes.
(b)[2 marks]Describe the shape of the solubility curve you draw.
Question 35
3 marks · Normal
Answer and see the solution →The solubility curve below shows that at 60°C, the solubility of sodium sulfate is 50 g per 100 g of water. At 30°C, its solubility is 30 g per 100 g of water.
Calculate the maximum mass of sodium sulfate that will dissolve in 250 g of water at 60°C. Show your working.
Question 36
3 marks · Normal
Answer and see the solution →A solution contains 90 g of ammonium nitrate dissolved in 100 g of water at 60°C. The solubility curve for ammonium nitrate shows that at 60°C, the solubility is 90 g per 100 g water, and at 30°C the solubility is 55 g per 100 g water.
Explain what happens as the solution is cooled from 60°C to 30°C. Calculate the mass of ammonium nitrate that will crystallise out. Show your reasoning.
Question 37
4 marks · Normal
Answer and see the solution →The following masses were recorded during a solubility experiment:
Measurement Mass (g) Mass of evaporating dish 18.50 Mass of dish + solution 53.40 Mass of dish + dry solid after evaporation 29.10 (a)[1 mark]Calculate the mass of solid obtained from the solution.
(b)[1 mark]Calculate the mass of water that was present in the solution.
(c)[2 marks]Calculate the solubility of the solid (in g per 100 g water) using your results.
Question 38
1 mark · Normal
Answer and check →Which feature must be present when plotting a solubility curve from data in a table?
- A.A line or curve smoothly joining the points
- B.Bars for each temperature
- C.An unlabelled vertical axis
- D.Dots connected only with straight lines
Question 39
2 marks · Normal
Answer and see the solution →The solubility of sodium carbonate in water at 10°C is 12 g per 100 g of water, and at 30°C is 18 g per 100 g of water. What would be the solubility at 30°C in 50 g of water? Give your answer in grams. Show your calculation.
Question 40
4 marks · Normal
Answer and see the solution →A solution contains 60.0 g of magnesium sulfate completely dissolved in 150 g of water at 70°C. The solubility curve for magnesium sulfate: at 70°C, solubility = 44 g/100 g water; at 30°C, solubility = 30 g/100 g water.
(a)[2 marks]Is the solution at 70°C saturated or unsaturated? Explain your answer.
(b)[1 mark]If the solution is cooled to 30°C and no water evaporates, calculate the maximum mass of magnesium sulfate that remains dissolved.
(c)[1 mark]Calculate the mass of magnesium sulfate that will crystallise out as the solution cools from 70°C to 30°C.