Final answer:
The pH of a 0.20 M CH3COOH (acetic acid) solution, if no salt is present, is 4.74.
Step-by-step explanation:
The pH of a 0.20 M CH3COOH (acetic acid) solution, if no salt is present, can be calculated using the ionization constant of acetic acid (Ka). The relationship between the concentration of H+ ions and the pH is given by the equation pH = -log[H+]. The ionization constant for acetic acid is 1.8 × 10^-5, and the initial concentration of acetic acid is 0.20 M. By using the equation pH = -log([H+]), we can calculate the pH:
pH = -log(1.8 × 10^-5) = 4.74