본문 바로가기
일반화학/[15장] 화학 평형

C6H5COOH(aq) + CH3COO^-(aq) ⇌ C6H5COO^-(aq) + CH3COOH(aq) is 3.6

by 영원파란 2021. 12. 7.

AdSense@ywpop

C6H5COOH(aq) + CH3COO^-(aq) ⇌ C6H5COO^-(aq) + CH3COOH(aq) is 3.6

 

 

The equilibrium constant for the reaction

C6H5COOH(aq) + CH3COO^-(aq) ⇌ C6H5COO^-(aq) + CH3COOH(aq)

is 3.6 at 25℃.

If Ka for CH3COOH is 1.8×10^(-5),

what is the acid dissociation constant for C6H5COOH?

 

---------------------------------------------------

▶ 참고: 이론적 평형상수

[ https://ywpop.tistory.com/4154 ]

---------------------------------------------------

 

C6H5COOH(aq) + CH3COO^-(aq) ⇌ C6H5COO^-(aq) + CH3COOH(aq)

K = [C6H5COO^-] [CH3COOH] / [C6H5COOH] [CH3COO^-]

 

 

 

CH3COOH(aq) ⇌ H^+(aq) + CH3COO^-(aq)

Ka1 = [H^+] [CH3COO^-] / [CH3COOH]

 

 

 

C6H5COOH(aq) ⇌ H^+(aq) + C6H5COO^-(aq)

Ka2 = [H^+] [C6H5COO^-] / [C6H5COOH]

 

 

 

H^+(aq) + CH3COO^-(aq) ⇌ CH3COOH(aq)

Ka3 = [CH3COOH] / [H^+] [CH3COO^-]

 

아세트산 이온화의 역반응이므로,

Ka3 = 1 / Ka1

 

 

 

 

Ka2 × Ka3 = K 이므로,

 

Ka2 = K / Ka3

= 3.6 / (1 / (1.8×10^(-5)))

= 6.5×10^(-5)

 

 

 

답: 6.5×10^(-5)

 

 

반응형
그리드형(광고전용)

댓글