A) 256 g \[mo{{l}^{-1}}\]
B) 2.56 g \[mo{{l}^{-1}}\]
C) \[512\times {{10}^{3}}g\,\,mo{{l}^{-1}}\]
D) \[2.56\times {{10}^{4}}g\,\,mo{{l}^{-1}}\]
Correct Answer: A
Solution :
Key Idea: Molecular mass of solute is calculated by using following formula \[M=\frac{{{K}_{f}}\times 100\times w}{\Delta {{T}_{f}}\times w}\] where, .M = molecular mass of solute w = mass of solute = 1.00 g \[\Delta {{T}_{f}}=\] depression in freezing point = 0.40 K W = mass of solvent = 50 g \[{{K}_{f}}=5.12\,kg/mol\] \[\therefore \] \[m=\frac{5.12\times 1000\times 1.00}{0.40\times 50}\] \[=256\,g\,mo{{l}^{-1}}\]You need to login to perform this action.
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