A) \[3.2\]
B) \[2\]
C) \[4\]
D) \[3.6\]
Correct Answer: A
Solution :
Let the solution be \[x\] molal then moles of solute present in 1000 g of benzene \[=\frac{1000}{78}=12.82\,\,moles\]. \[\therefore \]Mole fraction of solute\[=\frac{x}{x+12.82}\] \[0.2=\frac{x}{x+12.82}\] \[0.2(x+12.82)=x\] \[0.2x+2.564=x\] \[2.564=x-0.2x\] \[=0.8x\] \[x=\frac{2.564}{0.8}=3.2\]You need to login to perform this action.
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