Calculate the osmotic pressure at temperature `37^@C` of an aqueous solution of urea which freezes at `-0.52^@C`. Assume molality and molarity be numerically equal. `(K_f= 1.86^@C m^(-1)` )

Options

A. 720.5 atm
B. 7.1 atm
C. 71.1 atm
D. 0.85 atm

Answer

B

Explanation

Molality = `(DeltaT_f)/(K_f)=(0.52)/(1.86)`
`pi = CRT = (0.52)/(1.86)xx 0.0821 xx 310=7.1` atm