What is the pH of a 0.1 M solution of acetic acid (CH3COOH), given that its dissociation constant (Ka) is 1.8 x 10^-5?
Correct: C
To find the pH of the solution, we can use the formula pH = -log[H+]. First, we need to find the concentration of hydrogen ions [H+]. We can use the formula Ka = [H+][CH3COO-]/[CH3COOH] to find [H+]. Since the dissociation of acetic acid is weak, we can assume that [CH3COOH] remains approximately equal to the initial concentration (0.1 M). We can then solve for [H+] and subsequently find the pH.