JEE Main 2021 — Solutions Question with Solution
From: JEE Main 2021 (Online) 20th July Evening Shift
Question
The vapour pressures of A and B at 25C are 90 mm Hg and 15 mm Hg respectively. If A and B are mixed such that the mole fraction of A in the mixture is 0.6, then the mole fraction of B in the vapour phase is x 101. The value of x is ___________. (Nearest integer)
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Correct answer
1
Step-by-step explanation
xA = 0.6
PT = xAPAo + xBPBo
= 0.6 90 + 0.4 15
= 54 + 6 = 60
xAPAo = yAPT
0.6 90 = yA(60)
yA = 0.9
yB = 0.1 = 1 101
x = 1
PT = xAPAo + xBPBo
= 0.6 90 + 0.4 15
= 54 + 6 = 60
xAPAo = yAPT
0.6 90 = yA(60)
yA = 0.9
yB = 0.1 = 1 101
x = 1
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