The vapour pressure of benzene at `90^(@)C` is `1020` torr. A solution of `5 g` of a solute in `58.5 g` benzene has vapour pressure `990` torr. The molecualr weight of the solute is:A. (a) `78.2`B. (b) `178.2`C. ( c) `206.2`D. (d) `220`

The vapour pressure of benzene at `90^(@)C` is `1020` torr. A solution

1.	The vapour pressure of benzene at `90^(@)C` is `1020` torr. A solution of `5 g` of a solute in `58.5 g` benzene has vapour pressure `990` torr. The molecualr weight of the solute is:A. (a) `78.2`B. (b) `178.2`C. ( c) `206.2`D. (d) `220`
Answer» Correct Answer - D `(P^(@)-P_(S))/(P_(S)) = (w xx M)/(m xx W)` `(1020 - 990)/(990) = (5 xx 78)/(m xx 58.5)` `:. m = 220`

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The vapour pressure of benzene at `90^(@)C` is `1020` torr. A solution of `5 g` of a solute in `58.5 g` benzene has vapour pressure `990` torr. The molecualr weight of the solute is:A. (a) `78.2`B. (b) `178.2`C. ( c) `206.2`D. (d) `220`

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