Question

Two beakers of capacity 500 mL were taken. One of these
beakers labelled as "A" was filled with 400 mL water whereas
the beaker labelled "B" was filled with 400 mL of 2M solution
of NaCl. At the same temperature both the beakers were
placed in closed containers of same material and same
capacity as shown in figure.
Water
A B
NaCl solution
At a given temperature, which of the following statement is
correct about the vapour pressure of pure water and that of
NaCl solution?
(a) Vapour pressure in container (A) is more than that in
container (B)
(b) Vapour pressure in container (A) is less than that in
container (B)
(c) Vapour pressure is equal in both the containers
(d) Vapour pressure in container (B) is twice the vapour
pressure in container (A)

Answer 1

Answer:

order do their radii increase is not option of

(a) Ca²⁺ < Ar < K⁺

Answer 2

At the given conditions, from the data, the correct option is

a) Vapour pressure in container (A) is more than that in

container (B).

• Vapour pressure- The pressure exerted by the vapour thermodynamically in equilibrium with liquid phase.
• Always a liquid with pure components has greater vapour pressure due to absence of any other forces.
• Addition of a non voltaile solute in the water brings down the vapour pressure of the water, because of interactions between the solute molecules and the solvent molecules.
• So, Vapour pressure in container A is more than that in container B.