Answer:
To answer the question we will use the following equation:
[tex]Q=\Delta H_{vap}.n[/tex]Where:
Q is the energy we need to vaporize the substance
Hvap is he enthalpy of vaporization
n is the number of moles
We first calculate the number of moles by using the molar mass of CH2Cl2:
[tex]\begin{gathered} M_{CH_2Cl_2}=M_C+2M_H+2M_{Cl} \\ M_{CH_2Cl_2}=12\frac{g}{mol}+2.1\frac{g}{mol}+2.35.45\frac{g}{mol}=84.9\frac{g}{mol} \end{gathered}[/tex]We calculate n (number of moles):
[tex]n=\frac{92.3g}{84.9\frac{g}{mol}}=1.087mol[/tex]Now we calculate Q (energy)
[tex]Q=29.8\frac{kJ}{mol}.1.087mol=32.4kJ[/tex]So the answer is 32.4kJ