(1)第二周期第Ⅰ主族
(2)H 2(g)+1/2O 2(g)==H 2O(l) △H=-285.8KJ/mol
(3)
(4)①离子;②H ++HSO 3 -==H 2O+SO 2↑
(5)S 2-+ H 2O 2+ 2H +== S↓ +2H 2O
(1)第二周期第Ⅰ主族
(2)H 2(g)+1/2O 2(g)==H 2O(l) △H=-285.8KJ/mol
(3)
(4)①离子;②H ++HSO 3 -==H 2O+SO 2↑
(5)S 2-+ H 2O 2+ 2H +== S↓ +2H 2O