Reactivity series and displacement

WJEC Unit 1 — structured question

A student places small pieces of three different metals (X, Y, Z) into separate test tubes containing the same dilute acid. The observations are:

• Metal X: fizzes slowly; hydrogen gas produced over 2 minutes
• Metal Y: vigorous fizzing; hydrogen produced within seconds
• Metal Z: no reaction

(a) Place metals X, Y and Z in order of reactivity, most reactive first. (1 mark) (b) Predict what would happen if metal X were placed into a solution of Y's sulfate salt. Explain your answer in terms of electron transfer. (3 marks) (c) Write the ionic half-equations for the displacement of copper by zinc from copper sulfate solution. (3 marks)