`1`mol each of the following solutes are taken in `5`mol water,
(a)`NaCl` (b)`K_(2)SO_(4)`( C)`Na(3)PO_(4)`(d) glucose
Assuming `100%`ionisation of the electrolyte ,relative decrease in vapour pressure will be in order

Options

A. NaCl
B. `K_(2)SO_(4)`
C. `Na_(3)PO_(4)`
D. glucose

Answer

C

Explanation

Relative decrease in vapour pressure `propto` mole fraction of solute.
`{:("Solute","Mole in solution","Mole fraction of solute"),(A(NaCl)," "2," "(2)/(7)=0.29),(B(K_(2)SO_(4))," "3," "(3)/(8)=0.38),(C(N_(3)PO_(4))," "4," "(4)/(9)=0.44),(D("Glucose")," "1," "(1)/(6)=0.17):}`
Hence, `DltAltBltC`