Which of the following methods is used to obtain pure water from seawater?

The osmotic pressure of a $1 \ M$ solution at $27^{\circ}C$ is $(R = 0.082 \ L \ atm \ K^{-1} \ mol^{-1})$: (in $atm$)

Explain isotonic solutions.

If a solution has an osmotic pressure of $0.82 \ bar$ at $27 \ ^oC$,find the concentration of such a solution. (in $M$)

$A$ solution containing $10 \ g$ per $dm^3$ of urea (molecular mass $= 60 \ g \ mol^{-1}$) is isotonic with a $5 \%$ solution of a non-volatile solute. The molecular mass of this non-volatile solute is ........ $g \ mol^{-1}$.

$15 \%$ aqueous solution of glucose (molecular weight $= 180 \ g/mol$) is isotonic with $8 \%$ aqueous solution containing an unknown non-dissociable solute. What is the molecular weight of the unknown solute?