Gọi 2 kim loại là \(\overline M \)
\(\begin{array}{l}
\overline M C{O_3} + 2HCl \to \overline M C{l_2} + {H_2}O + C{O_2}\\
0,3 \leftarrow \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,0,3\\
\to \overline M + 60 = \dfrac{{39,6}}{{0,3}} \to \overline M = 72 \to Ca\,(40)\,;\,Sr\,(88)
\end{array}\)
