When solid `SnO_2` is added to an aqueous solution of NaOH, the

Options

A. vapour pressure is lowered.
B. vapour pressure is raised.
C. osmotic pressure is increased.
D. boiling point is raised.

Answer

B

Explanation

`2Na^(+)(aq) + 2OH^(-) (aq) + SnO_2(s) to 2Na^(+) (aq) + SnO_3^(-2) (aq) + H_2O`
The number of ions decreases in the ratio of 4 to 3, and so also the colligative property.