The osmotic pressure of $2.22\ \%\ (w/v)$ $CaCl_2$ solution at $27\ ^oC$ is $(R = 0.08\ L\ atm\ K^{-1}\ mol^{-1})$

Which of the following sets of solutions of urea (mol. mass $60 \ g \ mol^{-1}$) and sucrose (mol. mass $342 \ g \ mol^{-1}$) is isotonic?

At a constant temperature,the osmotic pressure of a solution is.....

What mass of solute (molar mass $58 \ g \ mol^{-1}$) is to be dissolved in $2.5 \ dm^3$ $H_2O$ to generate osmotic pressure of $0.245 \ atm$ at $300 \ K$ (in $g$)? $(R = 0.0821 \ dm^3 \ atm \ K^{-1} \ mol^{-1})$.

$300 \ mL$ of an aqueous solution of a protein contains $2.52 \ g$ of the protein. If the osmotic pressure of such a solution at $300 \ K$ is $5.04 \times 10^{-3} \ bar$,the molar mass of the protein in $g \ mol^{-1}$ is:

At a certain temperature,a $1.6 \%$ solution of an unknown substance is isotonic with a $2.4 \%$ solution of Urea. If both solutions have the same solvent and the same density of $1 \ g/cm^3$,what is the molecular mass of the unknown substance in $g/mol$? [Molecular mass of urea $= 60 \ g/mol$]