In the following reaction between lead sulphide and hydrogen peroxide :

(a) Which substance is reduced?

(b) Which substance is oxidised?

19 Which of the following is a combination and which is a displacement reaction?

(a)

(b)

20 What type of reactions are represented by the following equations?

(a)

(b)

(c)

(d)

(e)

22 Identify the component oxidised in the following reaction:

23 When S0₂ gas is passed through saturated solution of H₂S, the following reaction occurs :

In this reaction, which substance is oxidized and which one is reduced?