Em tham khảo nha :
\(\begin{array}{l}
2A + 2xHCl \to 2AC{l_x} + x{H_2}\\
{n_{{H_2}}} = \dfrac{{3,36}}{{22,4}} = 0,15mol\\
{n_A} = \dfrac{{2{n_{{H_2}}}}}{x} = \dfrac{{0,3}}{x}mol\\
{M_A} = 3,6:\dfrac{{0,3}}{x} = 12x\\
x = 2 \Rightarrow {M_A} = 24dvC\\
A:Magie(Mg)
\end{array}\)