Acetic acid, CH3CO2H, is the solute that gives vinegar its characteristic odor a
ID: 974030 • Letter: A
Question
Acetic acid, CH3CO2H, is the solute that gives vinegar its characteristic odor and sour taste. 1)Calculate the pH of 1.29 MCH3CO2H. 2)Calculate the concentration of H3O+ in 1.29 MCH3CO2H. 3)Calculate the concentration of CH3CO?2 in 1.29 MCH3CO2H. 4)Calculate the concentration of CH3CO2H in 1.29 MCH3CO2H. 5)Calculate the concentration of OH? in 1.29 MCH3CO2H. 6)Calculate the pH of 0.0229 MCH3CO2H. 7)Calculate the concentration of H3O+ in 0.0229 MCH3CO2H. 8)Calculate the concentration of CH3CO?2 in 0.0229 MCH3CO2H. 9)Calculate the concentration of CH3CO2H in 0.0229 MCH3CO2H. 10)Calculate the concentration of OH? in 0.0229 MCH3CO2H.
Explanation / Answer
1)
C = 1.29
Ka of acetic acid = 1.8 x 10^-5
pKa = 4.74
pH = 1/2 [pKa -logC]
pH = 1/2 [4.74- log 1.29]
pH = 2.31
2)
[H3O] = 10^-pH = 4.90 x 10^-3 M
[H3O] = 4.90 x 10^-3 M
3)
[CH3COO-] = x = 4.90 x 10^-3 M
4)
[CH3COOH] = 1.29 - 4.90 x10^-3 = 1.285 M
5)
[OH-] = Kw / [H3O+]
= 1.0 x10^-4 / 4.90 x 10^-3
= 2.04 x 10^-12 M
6)
pH = 3.19
7)
[H3O+] = 6.42 x 10^-4 M
8) [CH3COO-] = 6.42 x 10^-4 M
9) [CH3COOH] = 0.0223 M
10) [OH-] = 1.56 x 10^-11 M