Răspuns:
1.
H 2 + CI2→ 2 HCl
2 H 0 - 2 e - → 2 H I (oxidare) agent reducator
2 Cl 0 + 2 e - → 2 Cl -I (reducere) agent oxidant
2.
H2 + O2 → 2H2O
2 H 0 - 2 e - → 2 H I (oxidare) agent reducator
2 O 0 + 2 e - → 2 O - II ( reducere ) agent oxidant
3.
H2 + S → H2S
S 0 + 2 e - → S -II (reducere) agent oxidant
2 H 0 - 2 e - → 2 H I (oxidare) agent. reducator