Vapour pressure in mm Hg of 0.1 mole of urea in 180 g of water at `25^(@)C` is (The vapour pressure of water at `25^(@) C` is 24 mm Hg)

Options

A. 2.376
B. 20.76
C. 23.76
D. 24.76

Answer

( c)

Explanation

According to Raoults law.
`(P_(0)-P_(s))/(P_(0))=(w)/(m)xx(M)/(W)` (For very dilute solutions)
`(24-P_(s))/(24)=0.1xx(18)/(180)`
` therefore P_(s)=23.76`