Sea water is `3.5%`by mass of a salt and has a density `1.04gcm^(-3)` at `293K`.Assuming the salt to be sodium chloride ,calculate the osmotic pressure of sea water.Assume complete ionisation of the salt-

Options

A. 26.93 atm
B. 29.93 atm
C. 28.93 atm
D. 27.93 atm

Answer

B

Explanation

Mass of NaCl=`3.5g`
No. of moles=`(3.5)/(58.5)`
actual number of moles of particles of solute in solution=`(2xx3.5)/(58.5)`
Volume of solution `=(100)/(1.04xx1000)` litre
`pi=(2xx3.5)/(58.5)xx(1.04xx1000)/(100)xx0.0821xx293=29.93` atm.