A student wants to make pure, dry crystals of copper sulfate from copper oxide (an insoluble black powder) and dilute sulfuric acid.
Plan a method the student could use.
In your answer, explain the reason for each step.
[6 marks]Edexcel GCSE Combined Science November 2021 Chemistry Paper 1F
5 questions on this paper's topics
27:001 of 5
A student has samples of tap water, sea water and rain water.
Plan an investigation to compare the pH and the mass of dissolved solids in the three samples, and to purify the sea water by distillation.
[6 marks]Some metals are added to solutions of metal sulfates.
.1
Which two mixtures react? Tick two boxes.
[2 marks].2
Explain, in terms of ions, why magnesium is more reactive than zinc.
[2 marks]When ammonium chloride is heated it decomposes into ammonia and hydrogen chloride. On cooling, they react to form ammonium chloride again.
.1
The forward reaction takes in 176 kJ for each mole of ammonium chloride. Give the energy released when one mole of ammonium chloride forms from ammonia and hydrogen chloride.
[1 mark].2
Explain why ammonium chloride reforms at the cool top of a test tube when it is heated at the bottom.
[2 marks]Sodium chloride melts at 801 °C. It does not conduct electricity when solid, but it does when molten.
.1
Explain why sodium chloride has a high melting point.
[2 marks].2
Explain why molten sodium chloride conducts electricity but solid sodium chloride does not.
[2 marks]