Answer the case-based question given below.
Redox reactions are those reactions in which oxidation and reduction occur simultaneously. A redox reaction is made up of two half reactions.
In the first half reaction, oxidation takes place and in second half reaction, reduction occurs. Oxidation is a process in which a substance loses electrons and in reduction, a substance gains electron.
The substance which gains electrons is reduced and acts as an oxidising agent. On the other hand, a substance which loses electrons is oxidised and acts as a reducing agent.
In the first half reaction, oxidation takes place and in second half reaction, reduction occurs. Oxidation is a process in which a substance loses electrons and in reduction, a substance gains electron.
The substance which gains electrons is reduced and acts as an oxidising agent. On the other hand, a substance which loses electrons is oxidised and acts as a reducing agent.
a. When copper powder is heated and turns black, which statement correctly explains the observation?
b. In the reaction, \(CuO + H_2 → Cu + H_2O\) which species acts as the reducing agent?
c. In the following reaction, which substance is oxidised?
\(ZnO + CO ⟶ Zn + CO_2\)
\(ZnO + CO ⟶ Zn + CO_2\)
d. In the following reaction, which substance is reduced?
\(PbS + 4H_2O_2 ⟶ PbSO_4 + 4H_2O\)
\(PbS + 4H_2O_2 ⟶ PbSO_4 + 4H_2O\)