Addition of 0.643g of a compound to 43.95g of benzene lowers the freezing point from `5.51^@`C to `5.03^@`C. If `K_f` for benzene is 5.12K kg `mol^-1` , calculate the molar mass of the compound.

Options

A. 0.02 kg/mol
B. 0.001 kg/mol
C. 0.003 kg/mol
D. 1 kg/mol

Answer

d

Explanation

(d) `U_("rms")=sqrt((3RT)/(M)`