Đáp án:
C. 2,3,4
Giải thích các bước giải:
\(\begin{array}{l}
S{O_2} + {H_2}O \to {H_2}S{O_3}\\
C{O_2} + {H_2}O \to {H_2}C{O_3}\\
{N_2}{O_5} + {H_2}O \to 2HN{O_3}\\
S{O_2} + NaOH \to NaHS{O_3}\\
C{O_2} + NaOH \to NaHC{O_3}\\
{N_2}{O_5} + 2NaOH \to 2NaN{O_3} + {H_2}O\\
N{a_2}O + {H_2}O \to 2NaOH\\
CaO + {H_2}O \to Ca{(OH)_2}\\
A{l_2}{O_3} + 6HCl \to 2AlC{l_3} + 3{H_2}O\\
MgO + 2HCl \to MgC{l_2} + {H_2}O\\
CuO + 2HCl \to CuC{l_2} + {H_2}O\\
{K_2}O + {H_2}O \to 2KOH\\
N{a_2}O + 2HCl \to 2NaCl + {H_2}O\\
CaO + 2HCl \to CaC{l_2} + {H_2}O\\
{K_2}O + 2HCl \to 2KCl + {H_2}O
\end{array}\)
