Question

1) All of the following are oxidation-reduction reactions except
(a) 2Al(s) + Fe2O3(s) ---> A12O3(s) + 2Fe(s)
(b) (NH4)2Cr2O7(s) ---> Cr2O3(s) + N2(g) + H2O(1)
(c) Cu(s) + 2H2SO4(aq) ---> CuSO4(aq) + SO2(g) + 2H2O(1)
(d) Hg(NO3)2 + 4KI ---> K2HgI4(aq) +
2 KNO3(aq)
(e) 2Na(s) + 2H2O(1) --> 2NaOH(aq) +
H2(g)

Answer 1

This is a matter of going through each equation and determining the oxidation state of each, then comparing to see if any have changed. If not, that will answer your question.
1. Al is 0 on the left and +3 on the right. Therefore, this is an oxidation/reduction equation.
etc.