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)
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.
