The equilibrium constant for the reaction C₆H₅COOH(aq) + CH₃COO^-(aq)
C₆H₅COO^-(aq) + CH₃COOH(aq)
Is 3.6 at 25°C.If K_a for CH₃COOH is 1.8 × 10^-5, what is the acid dissociation constant for C₆H₅COOH?

Question

The equilibrium constant for the reaction C₆H₅COOH(aq) + CH₃COO^-(aq)

The equilibrium constant for the reaction C<sub>6</sub>H<sub>5</sub>COOH(aq) + CH<sub>3</sub>COO<sup>-</sup>(aq) <sub> </sub> C<sub>6</sub>H<sub>5</sub>COO<sup>-</sup>(aq) + CH<sub>3</sub>COOH(aq) Is 3.6 at 25°C.If K<sub>a</sub> for CH<sub>3</sub>COOH is 1.8 × 10<sup>-5</sup>, what is the acid dissociation constant for C<sub>6</sub>H<sub>5</sub>COOH? A) 5.0 × 10<sup>-6</sup> B) 6.5 × 10<sup>-5</sup> C) 2.3 × 10<sup>-4</sup> D) 8.3 × 10<sup>-5</sup> E) 5.6 × 10<sup>-6</sup>

C₆H₅COO^-(aq) + CH₃COOH(aq)
Is 3.6 at 25°C.If K_a for CH₃COOH is 1.8 × 10^-5, what is the acid dissociation constant for C₆H₅COOH?

Quizplus · Accepted Answer

The acid dissociation constant (Ka) for the given reaction is equal to the ion product constant (KW) divided by the equilibrium constant (Kc) for the reaction.

KW = 1.0 × 10^-14 (at 25°C)
Kc = 3.6 (given)

Therefore, Ka = KW/Kc = 1.8 × 10^-5 / 3.6 = 5.0 × 10^-6

The closest choice to this value is B, 6.5 × 10^-5, making it the correct answer.

The Equilibrium Constant for the Reaction C6H5COOH(aq)+ CH3COO-(aq)

The Equilibrium Constant for the Reaction C₆H₅COOH(aq)+ CH₃COO^-(aq)