Question

Which of the following is an oxidation-reduction reaction? ZnS(s) + 2O2(g) mc011-1.jpg ZnSO4(s) CaO(s) + H2O(l) mc011-2.jpg Ca(OH)2(s) 6Li2O(s) + P4O10(g) mc011-3.jpg 4Li3PO4(s) SO2(g) + H2O(l) mc011-4.jpg H2SO3(aq)

Answer 1

Answer;

ZnS(s) + 2O2(g) → ZnSO4(s)

Explanation;

• Oxidation involves the loss of electrons while reduction is the gaining of electrons. Oxidation-reduction reaction is a reaction which involves the gaining of electrons and loss of electrons.
• Oxidation may also be referred to as increase in the oxidation state of an atom while reduction is the decrease of oxidation state of an atom.
• The reaction ZnS(s) + 2O2(g) → ZnSO4(s) is an example of a redox reaction or what we call oxidation-reduction reaction.
• The oxidation number of sulfur in ZnS is -2, while the oxidation number of sulfur in ZnSO₄ is 4. This means sulfur has undergone oxidation.
• The oxidation number of oxygen in oxygen gas is Zero, and its oxidation number in ZnSO₄ is -2, therefore oxygen has undergone reduction.

Answer 2

ZnS(s) + 2O2(g) mc011-1.jpg ZnSO4(s) CaO(s) + H2O(l)