18 g of glucose `(C_(6)H_(12)O_(6))` is added to 178.2 g of water. The vapour pressure of water for this aqueous solution at `100^(@)C` is :

Options

A. 7.60 torr
B. 76.00 torr
C. 752.40 torr
D. 759.00 torr

Answer

C

Explanation

`(p^(@)-p)/(p^(@))=x`(solute)
`p^(@)`, vapour pressure of pure water at `100^(@)C`
`=760` torr
`x=((18)/(180))/((18)/(180)+(178*2)/(18))=(0*1)/(0*1+9*9)=(0*1)/(10)`
`:.(0*1)/(10)=(760-p)/(760)`
Solving `p=752*4` torr.