Chemistry - Chemical Equilibrium Question with Solution | TestHub
When 1.0 mole of trichloroacetic acid and 5.0 moles of propene were heated together at 373 K to equilibrium, 0.5 mole of ester was formed and the total volume of the mixture was 500 mL. In another experiment, 1.0 mole of the acid was heated at the same temperature with some moles of propene and the equilibrium mixture occupied a volume of 400 mL. If the amount of ester at equilibrium is 0.6 mole in the second experiment, how many moles of propene were taken initially?
Answer:
Solution:
Reaction: acid + propene ⇌ ester First experiment: acid = 0.5 mol, propene = 4.5 mol, ester = 0.5 mol, V = 0.5 L
Kc = (0.5/0.5)/[(0.5/0.5)(4.5/0.5)] = 0.5/4.5 = 1/9 L/mol
Second experiment: acid = 0.4 mol, ester = 0.6 mol, propene = y - 0.6, V = 0.4 L
Kc = (0.6)(0.4)/[0.4(y-0.6)] = 1/9
y - 0.6 = 9(0.6) = 5.4
y = 6 mol
