Em tham khảo nha:

\(\begin{array}{l}
1)\\
2K + 2{H_2}O \to 2KOH + {H_2}\\
2Na + 2{H_2}O \to 2NaOH + {H_2}\\
Ba + 2{H_2}O \to Ba{(OH)_2} + {H_2}\\
Ca + 2{H_2}O \to Ca{(OH)_2} + {H_2}\\
2)\\
CaO + {H_2}O \to Ca{(OH)_2}\\
BaO + {H_2}O \to Ba{(OH)_2}\\
N{a_2}O + {H_2}O \to 2NaOH\\
{K_2}O + {H_2}O \to 2KOH\\
3)\\
S{O_2} + {H_2}O \to {H_2}S{O_3}\\
S{O_3} + {H_2}O \to {H_2}S{O_4}\\
{P_2}{O_5} + 3{H_2}O \to 2{H_3}P{O_4}\\
{N_2}{O_5} + {H_2}O \to 2HN{O_3}
\end{array}\)

Đáp án:

1)2K+2H2O→2KOH+H22Na+2H2O→2NaOH+H2Ba+2H2O→Ba(OH)2+H2Ca+2H2O→Ca(OH)2+H22)CaO+H2O→Ca(OH)2BaO+H2O→Ba(OH)2Na2O+H2O→2NaOHK2O+H2O→2KOH3)SO2+H2O→H2SO3SO3+H2O→H2SO4P2O5+3H2O→2H3PO4N2O5+H2O→2HNO3