At $$T(\mathrm{~K}) \times \mathrm{g}$$ of a non-volatile solid (molar mass $$78 \mathrm{~g} \mathrm{~mol}^{-1}$$) when added to 0.5 kg water, lowered its freezing point by $$1.0^{\circ} \mathrm{C}$$. What is $$x$$ (in g)? ($$K_f$$ of water at $$T(\mathrm{~K})=1.86 \mathrm{~K} \mathrm{~kg} \mathrm{~mol}^{-1}$$)

Assertion (A) Blood cells collapse when suspended in saline water.

Reason (R) Cell membrane dissolves in saline water.

If two liquids $$A$$ and $$B$$ form a minimum boiling azeotrope at some specific composition, then which statement among the following is correct?

The vapour pressure of a solvent decreased by 20 mm of Hg when a non-volatile solute was added to the solvent. The mole fraction of the solute in the solution is 0.5. What should be the mole fraction of the solvent for the decrease in the vapour pressure needs to be 10 mm of Hg?