Explain why on addition of 1 mol of NaCl to 1 litre of water, the boiling point of water increases, while addition of 1 mol of methyl alcohol to one litre of water decreases its boiling point.

State Henry’s Law and write its two application?

Using Raoult’s law explain how the total vapour pressure over the solution is related to the mole fraction of components in the following solutions.

(i) CHCl₃ (l) and CH₂Cl₂(l)

(ii) NaCl(s) and H2O (l)

Write one stereochemical difference between SN₁ and SN₂?

Note: In the following questions a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.

Assertion: When NaCl is added to water a depression in freezing point is observed.

Reason: The lowering of the vapour pressure of a solution causes depression in the freezing point.

When 1 mol of NaCl is added to 1 litre of water, the boiling point of water increases. On the other hand, addition of 1 mol of methyl alcohol to one litre of water decreases the boiling point of water. Explain why does this happen.