What is the change in the oxidation number of copper in the reaction?

Cu2S(g) + O2(g) → 2Cu + SO2(g)

A. 0 to + 2
B. 0 to + 1
C. + 1 to 0
D. + 2 to + 1

Correct Answer:

Option C = + 1 to 0

Explanation

In the reactant;

Cu2S

2Cu – 2(1) = 0

2Cu = 2

Cu = 2/2

Cu = +1

In the product, Cu

Cu = O

The oxidation number of Cu in Cu2S and Cu respectively is +1 and 0 respectively