Osmotic pressure of a urea solution at `10^(@)C` is 500 mm. Osmotic pressure of the solution become 105.3 mm. When it is diluted and temperature raised to `25^(@)C`.The extent of dilution is

Options

A. 6 Times
B. 5 Times
C. 7 Times
D. 4 Times

Answer

B

Explanation

Let conc. C beX
`pi = CRT `
`105 = x xxR xx 298` …..i
When the conc. of solution increases by n times
`500= nx xx R xx 298` …ii
Dividing ii by I,
`( 500)/( 105) = ( nx xx R xx283)/( x xx R xx 298)`
`( 500xx 298 )/ ( 105 xx283) =n `
n gives how many times the solution was concentrated to get osmotic pressure 500 mm , at `25^(@)C`.
The same number of times the solution was diluted to get osmotic pressure 105 mm at `10^(@)C `.