Which among the following gases exhibits very low solubility in water at room temperature?

$$0.2 ~\mathrm{M}$$ aqueous solution of glucose has osmotic pressure 4.9 atm at $$300 \mathrm{~K}$$. What is the concentration of glucose if it has osmotic pressure $$1.5 \mathrm{~atm}$$ at same temperature?

A solution of nonvolatile solute is obtained by dissolving $$3.5 \mathrm{~g}$$ in $$100 \mathrm{~g}$$ solvent has boiling point elevation $$0.35 \mathrm{~K}$$. Calculate the molar mass of solute.

(Molal elevation constant $$=2.5 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}$$ )

Calculate the solubility of a gas in water at $$0.8 \mathrm{~atm}$$ and $$25^{\circ} \mathrm{C}$$.

[Henry's law constant is $$6.85 \times 10^{-4} \mathrm{~mol} \mathrm{~dm}^{-3} \mathrm{~atm}^{-1}$$ ]