Chemistry - Chemical Equilibrium Question with Solution | TestHub
Equimolar mixture of two gases A2 and B2 is taken in a rigid vessel at constant temperature 400 K. The gases achieve equilibrium as:
A2(g) ⇌ 2A(g), KP = x atm
B2(g) ⇌ 2B(g), KP = y atm
A2(g) + B2(g) ⇌ 2AB(g), KP = 3
If the initial pressure in the container was 9 atm and the final pressure at equilibrium is 11.5 atm in which the partial pressure of AB(g) is 3 atm, and y > x, the value of y:x is
Answer:
Solution:
Initial pressures: A2 = B2 = 4.5 atm Let PA = a and PB = b
PA2 = 4.5 - a/2 - 1.5 = 3 - a/2 and PB2 = 3 - b/2
Total = PA2 + PB2 + a + b + 3 = 9 + (a+b)/2 = 11.5, so a + b = 5
KP = (3)2/(PA2PB2) = 3, so PA2PB2 = 3
PA2 + PB2 = 6 - 2.5 = 3.5
t2 - 3.5t + 3 = 0, so the pressures are 2 and 1.5 atm
y > x requires PA2 = 2 (a = 2) and PB2 = 1.5 (b = 3)
x = a2/PA2 = 4/2 = 2 atm
y = b2/PB2 = 9/1.5 = 6 atm
y:x = 6/2 = 3, written as 0003
