\(n_{Na_2O}=\dfrac{9.3}{62}=0.15\left(mol\right)\)
\(Na_2O+H_2O\rightarrow2NaOH\)
\(0.15........................0.3\)
\(C_{M_{NaOH}}=\dfrac{0.3}{0.4}=0.75\left(M\right)\)
\(n_{Ha_2O}=\dfrac{9.3}{62}=0.15Z\left(mol\right)\)
\(Na_2O+H_2O\rightarrow2NaOH\)
\(0.15....................................0.3\)
\(C_{M_{NaOH}}=\dfrac{0.3}{0.4}=0.15\left(M\right)\)