Explanation:
It is given that the initial mass of benznene is 7.9286 g
Mass of benzene left = 5.9987 g
So, mass of benzene with which gas get saturated will be calculated as follows.
        = 7.9286 g  - 5.9987 g  = 1.9299 g
Therefore, moles of benzene with which gas get saturated = [tex]\frac{mass}{ molar mass}[/tex]
        = [tex]\frac{1.9299 g}{78.112 g/mol}[/tex]
        = 0.0247 moles
Temperature = [tex]27.3^{o}C[/tex] = 27.3 + 273.15 = 300.45 K
Volume = 5.01 L
So, according to ideal gas equation PV = nRT
Putting the given values into the ideal gas equation as follows.
            PV = nRT
      [tex]P \times 5.01 L[/tex] = [tex]0.0247 mol \times 62.36 torr-liter/mol K \times 300.45 K[/tex]
          P = [tex]\frac{462.781 torr-liter}{5.01 L}[/tex]
           = 92.371 torr
Hence, we can conclude that vapor pressure of benzene is 92.371 torr.