# The molar mass of acetic acid dissolved in benzene determined from the depression in freezing point is found to be

$\begin{array}{1 1} 30\;g\;mol^{-1} \\ 60\;g\;mol^{-1} \\ 120\;g\;mol^{-1} \\ 240\;g\;mol^{-1} \end{array}$

Answer : $120\;g\;mol^{-1}$
Acetic acid dimerizes in benzene, Its molar mass would be $2 \times 60\;g\;mol^{-1}$, i.e $120\;g\;mol^{-1}$
edited Aug 6, 2014 by meena.p