The rise in boiling point of a solution containing $$1.8 \mathrm{~g}$$ of glucose in $$100 \mathrm{~g}$$ of solvent is $$0.1^{\circ} \mathrm{C}$$. The molal elevation constant of the liquid is

If $$3 \mathrm{~g}$$ of glucose (molar mass $$=180 \mathrm{~g}$$) is dissolved in $$60 \mathrm{~g}$$ of water at $$15^{\circ} \mathrm{C}$$, the osmotic pressure of the solution will be

Which of the following colligative properties can provide molar mass of proteins, polymers and colloids with greater precision?

Henry's law constant for the solubility of $$\mathrm{N}_2$$ gas in water at $$298 \mathrm{~K}$$ is $$1.0 \times 10^5 \mathrm{~atm}$$. The mole fraction of $$\mathrm{N}_2$$ in air is 0.8 . The number of moles of $$\mathrm{N}_2$$ from air dissolved in 10 moles of water at $$298 \mathrm{~K}$$ and $$5 \mathrm{~atm}$$ pressure is