WAEC Chemistry 2024 Paper

Ni‌2+‌aq + Fe‌s → Ni‌s + Fe‌2+‌aq

Reduction takes place from Ni‌2+ to Ni because there is a decrease in oxidation number from +2 to 0. Thus, Ni‌2+ ions are reduced to Ni

Oxidation takes place from Fe to Fe‌2+ because there is an increase in oxidation number from 0 to +2. Thus, Fe is oxidized to Fe‌2+

Oxidizing agent → Ni‌2+ because oxidizing agents undergo reduction.

Reducing agent → Fe because reducing agents undergo oxidation.

Consequently, option D is the correct option.