Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Section
Solubility curves
19 practice questions
Practice questions
1–3 of 3 · Hard
Question 1
2 marks · Hard
Answer and see the solution →A student obtains the following measurements while investigating the solubility of a solid in water: Mass of empty dish = 22.35 g Mass of dish + solution = 58.20 g Mass of dish + dry crystals = 39.10 g Calculate the solubility of the solid in 100 g of water at this temperature. Show your working.
Question 2
5 marks · Hard
Answer and see the solution →The table below shows the solubility of sodium sulfate at different temperatures.
Solubility of sodium sulfate at different temperatures Temperature /°C Solubility / g per 100 g of water 10 12.5 30 19.6 50 29.4 70 40.8 90 53.1 (a)[2 marks]On graph paper, plot a solubility curve for sodium sulfate using the data in the table. Label the axes appropriately.
(b)[1 mark]Estimate the solubility of sodium sulfate at 60°C using your curve.
(c)[2 marks]Describe the trend shown by the solubility curve as temperature increases.
Question 3
2 marks · Hard
Answer and see the solution →The solubility curve for potassium nitrate shows the following data: At 25°C, solubility = 38 g per 100 g of water At 60°C, solubility = 109 g per 100 g of water A solution is prepared by dissolving 70 g of potassium nitrate in 100 g of water at 60°C. Use the solubility curve to determine the temperature at which crystals of potassium nitrate will begin to form when this solution is cooled.