Question

A 0.100 m solution of which one of the following solutes will have the highest vapor pressure? A 0.100 m solution of which one of the following solutes will have the highest vapor pressure? KClO4 Ca(ClO4)2 NaCl sucrose Al(ClO4)3

Answer 1

Explanation:

Vapor pressure is defined as the pressure exerted by vapors or gas on the surface of a liquid.

Vapor pressure is inversely proportional to the number of solute particles. Hence, more will be the solute particles lower will be the vapor pressure and vice-versa.

(a)   $KClO_{4} \rightarrow K^{+} + ClO^{-}_{4}$

It dissociates to give two particles.

(b)  $Ca(ClO_{4})_{2} \rightarrow Ca^{2+} + 2ClO^{-}_{4}$

Total number of particles it give upon dissociation are 1 + 2 = 3. Hence, it gives 3 particles.

(c)   $Al(ClO_{4})_{3} \rightarrow Al^{3+} + 3ClO^{-}_{4}$

Total number of particles it give upon dissociation are 1 + 3 = 4. Hence, it gives 4 particles.

(d)  Surcose being a cobvalent compound doe not dissociate into ions. Therefore, there will be only 1 particle is present.

(e)   $NaCl \rightarrow Na^{+} + Cl^{-}$

Total number of particles it give upon dissociation are 1 + 1 = 2. Hence, it gives 2 particles.