4. Identify which of the following are oxidation-reduction reactions. If a reaction is a redox reaction, name the element oxidized and the element reduced.

C. CaCO3(s) + 2HCl(aq) – CaCl(aq) + H2011+ CO,19)

D. CuO(s) + H2(g) - Cu(s) + H2O(1)

E. Li(s) + H2011 – LiOH(aq) + H2(g)