JEE Main 2021 — Solutions Question with Solution
From: JEE Main 2021 (Online) 18th March Evening Shift
Question
A solute A dimerizes in water. The boiling point of a 2 molal solution of A is 100.52C. The percentage association of A is __________. (Round off to the Nearest Integer).
[Use : Kb for water = 0.52 K kg mol1 Boiling point of water = 100C]
[Use : Kb for water = 0.52 K kg mol1 Boiling point of water = 100C]
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Show full solutionCorrect answer: 100
Correct answer
100
Step-by-step explanation
Tb = Boiling point of the solution Boiling point of the pure solvent
= 100.52 100
= 0.52
Tb = Kb (iM)
0.52 = i 0.52 2
i =
We know,
i = 1 +
here, = degree of dimerization
n = number of particle associated
n = 2 for dimerization
% association = 100
= 100.52 100
= 0.52
Tb = Kb (iM)
0.52 = i 0.52 2
i =
We know,
i = 1 +
here, = degree of dimerization
n = number of particle associated
n = 2 for dimerization
% association = 100
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