Question

At T(K), 3 moles of ethyl alcohol is mixed with 3 moles of acetic acid in a 1L vessel. At equilibrium, 2 moles of ester are formed. Calculate the equilibrium constant for the reaction.

• A. 4
• B. 2/9
• C. 2
• D. 4/9

Hint:

The equilibrium constant (K) helps predict the extent of reaction under specified conditions and is crucial for understanding reaction dynamics.

Answer 1

The Correct Option is A

Step 1: Establish initial conditions and changes at equilibrium. Initial conditions set at 3 moles each for reactants with no ester or water. At equilibrium, formation of 2 moles of ester and water reduces reactants by 2 moles each. 
Step 2: Calculate equilibrium concentrations and derive K. Given the reaction in a 1L vessel, equilibrium concentrations are directly equal to the moles at equilibrium: \[ [C_2H_5OH] = 1 { M}, [CH_3COOH] = 1 { M}, [CH_3COOC_2H_5] = 2 { M}, [H_2O] = 2 { M} \] \[ K = \frac{[CH_3COOC_2H_5][H_2O]}{[C_2H_5OH][CH_3COOH]} = \frac{2 \times 2}{1 \times 1} = 4 \]