QCEVault

Chemical equilibrium — Question 92

Original QCE Vault practice · 6 marks

Q92 · Practice questionComplex unfamiliar6 marks

QUESTION 92 (6 marks)

Ethanoic acid reacts with ethanol in a non-aqueous homogeneous mixture of constant volume 100.0 mL. Initially each reactant has concentration 0.100 mol L⁻¹ and neither product is present. For this model, Kc=[ester][H2O][acid][ethanol]=4.00. The ester molar mass is 88.1 g mol⁻¹.

a) Calculate the equilibrium ester concentration. [3 marks]

b) Calculate the equilibrium ester mass and its percentage of the stoichiometric maximum yield. [2 marks]

c) Explain the effect of removing water as it forms. [1 marks]

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