Which of the following is an excellent semipermeable membrane?

The osmotic pressure of blood at $300 \ K$ is $8.21 \ atm$. What is the concentration of an aqueous glucose solution that is isotonic with this blood in $g \ L^{-1}$?

The osmotic pressures of $0.010 \ M$ solutions of $KI$ and of sucrose $(C_{12}H_{22}O_{11})$ are $0.432 \ atm$ and $0.24 \ atm$ respectively. The van't Hoff factor for $KI$ is

The osmotic pressure of sea water is $1.05 \ atm$. Four experiments were carried out as shown in the table below. In which of the following experiments can pure water be obtained in part-$II$ of the vessel?
| Experiment | Pressure applied on part-$I$ $(atm)$ | Pressure applied on part-$II$ $(atm)$ |
| :--- | :--- | :--- |
| $I$ | $2.0$ | $1.0$ |
| $II$ | $1.0$ | $2.0$ |
| $III$ | $3.0$ | $1.0$ |
| $IV$ | $1.0$ | $1.0$ |

Calculate the osmotic pressure exerted by a solution containing $0.822 \ g$ of solute in $300 \ mL$ of water at $300 \ K$. (Molar mass of solute $= 340 \ g \ mol^{-1}, R = 0.0821 \ L \ atm \ mol^{-1} \ K^{-1}$) (in $atm$)

$A$ solution containing $10 \ g$ of urea (molar mass $= 60 \ g \ mol^{-1}$) per liter is isotonic with a $5 \% \ w/v$ solution of a non-volatile solute. The molar mass of the non-volatile solute is ......... $g \ mol^{-1}$.