Practicals

Question 1

How do you do the making salts practical?

Answer 1

1. Add excess insoluble metal oxide (e.g. copper(II) oxide) to warm dilute acid (e.g. sulfuric acid). 2. Stir until no more reacts (indicating neutralisation is complete). 3. Filter the mixture to remove excess solid. 4. Heat the filtrate to evaporate some water. 5. Leave to crystallise. 6. Dry the crystals using filter paper.

Question 2

How do you do the electrolysis practical?

Answer 2

1. Set up a circuit with two inert electrodes in an aqueous solution (e.g. sodium chloride). 2. Connect the electrodes to a power supply. 3. Observe or test the products at each electrode. 4. At the cathode, hydrogen or metal forms depending on reactivity. 5. At the anode, oxygen or halogen forms depending on the ions present.

Question 3

How do you do the temperature change (exothermic) practical?

Answer 3

1. Use a polystyrene cup in a beaker for insulation. 2. Measure a fixed volume of hydrochloric acid into the cup. 3. Record the initial temperature. 4. Add a measured volume of sodium hydroxide solution. 5. Stir and record the highest temperature reached. 6. Calculate the temperature change. 7. Repeat and take an average for accuracy.