# Problem: Calculate the pH of a 0.40 M solution of sodium acetate (NaCH3COO) given that the Ka of acetic acid (CH3COOH) is 1.8 x 10-5.a. 2.96b. 4.68c. 3.32d. 9.26e. 3.14

###### FREE Expert Solution

We are being asked to calculate the pH of a 0.40 M solution of sodium acetate (NaCH3COO) given that the Ka of acetic acid (CH3COOH) is 1.8 x 10-5.

NaCH3COO is a salt and it will break up in the solution:

NaCH3COO → Na+(aq) + CH3COO-(aq)

CH3COO- is the conjugate base of a weak acid (CH3COOH):

CH3COOH    +   H2O(l)    →    CH3COOH-(aq)    +     H3O+(aq)
(weak acid)                                  (conjugate base)

Since we’re dealing with a weak base, we will have to create an ICE chart to determine the equilibrium concentration of each species:

CH3COO-weak baseproton acceptor
H2O → will act as the weak acidproton donor

Equilibrium reaction:        CH3COO-(aq) + H2O(l)  CH3COOH(aq) + OH-(aq) ###### Problem Details

Calculate the pH of a 0.40 M solution of sodium acetate (NaCH3COO) given that the Ka of acetic acid (CH3COOH) is 1.8 x 10-5.

a. 2.96
b. 4.68
c. 3.32
d. 9.26
e. 3.14