$$12\,g$$ of urea is dissolved in 1 litre of water and $$68.4\,g$$ of sucrose is dissolved in 1 litre of water. The lowering of vapour pressure of first case is
A.
equal to second
B.
greater than second
C.
less than second
D.
double that of second
Answer :
equal to second
Solution :
$$\eqalign{
& {\text{Moles of urea}} = \frac{{12}}{{60}} = 0.2 \cr
& {\text{Moles of sucrose}} = \frac{{68.4}}{{342}} = 0.2 \cr} $$
Both are non electrolyte hence lowering of $$V.P.$$ will be same.
Releted MCQ Question on Physical Chemistry >> Solutions
Releted Question 1
An azeotropic solution of two liquids has boiling point lower than either of them when it