Which of the following reactions represents the laboratory preparation of hydrogen?
- C(s) + H 2 O(l) → CO(g) + H2(g)
- 2Na(s) + 2H2O(l) → 2NaOH(aq) + H2(g)
-
Zn(s) + 2HCI(aq) → ZnCI2(aq) + H2(g)
- Cu(s) + H2O(l) → CuO(s) + H2(g)
- 2AI(s) + 3H2O(l) → Al2O3(s) + 3H2(g)