If w2 gram of the solute having molar mass as M2, present in w1
gram of solvent, produces the depression in freezing point DTf of the
solvent then molality of the solute is given by the equation (1 31) m
= w
w
2
2
1
 / 
 
/1000
M
(1 31)
Substituting this value of molality in equation (1