Solutions Question 65
Question: The freezing point of a solution prepared from $ 1.25,gm $ of a non-electrolyte and $ 20,gm $ of water is $ 271.9,K $ . If molar depression constant is $ 1.86K,mol{e^{-1}} $ , then molar mass of the solute will be [AFMC 1998; CPMT 1999]
Options:
A) 105.7
B) 106.7
C) 115.3
D) 93.9
Show Answer
Answer:
Correct Answer: A
Solution:
Molar mass $ =\frac{K_{f}\times 1000\times w}{\Delta T_{f}\times W}=\frac{1.86\times 1000\times 1.25}{20\times 1.1} $
$ =105.68=105.7 $ .