Write balanced equations and name the products formed when:
(a) Sodium hydrogen carbonate is added to nitric acid
(b) cupric oxide reacts with nitric acid
(c) zinc reacts with dilute nitric acid
(d) concentrated nitric acid is heated

(a) When Sodium hydrogen carbonate is added to nitric acid sodium nitrate, carbon dioxide and water is formed.

$NaHC{O}_3+HN{O}_3⟶NaN{O}_3+H_{2}O+C{O}_2$

(b) When Cupric oxide reacts with dilute nitric acid, it forms Copper nitrate.

$CuO+2HN{O}_3⟶Cu(N{O}_3{)}_2+H_{2}O$

(c) Zinc reacts with nitric acid to form Zinc nitrate, nitric oxide and water.

$3Zn+8HN{O}_3⟶3Zn(N{O}_3{)}_2+4H_{2}O+2NO$

(d) $4HN{O}_3⟶2H_{2}O+4N{O}_2+O_2$