Coi \(m_{ddZnCl_2}=100\left(g\right)\) \(\Rightarrow\left\{{}\begin{matrix}n_{ZnCl_2}=\dfrac{100\cdot25\%}{136}=\dfrac{25}{136}\left(mol\right)\\V_{ddZnCl_2}=\dfrac{100}{1,23}=\dfrac{10000}{123}\left(ml\right)\end{matrix}\right.\)
\(\Rightarrow C_{M_{ZnCl_2}}=\dfrac{\dfrac{25}{136}}{\dfrac{10}{23}}\approx0,42\left(M\right)\)