Final answer:
The hydroxide ion concentration ([OH−]) in a 0.32 M HCl solution is approximately 3.125 × 10−13 M, and the pH of the solution is around 0.50, considering that HCl is a strong acid and dissociates completely in water.
Step-by-step explanation:
Calculating [OH−] and pH in a HCl Solution
To find the hydroxide ion concentration ([OH−]) in a 0.32 M solution of hydrochloric acid (HCl), we must understand that HCl is a strong acid and therefore fully dissociates in water. Since it releases one hydrogen ion (H+) per molecule of acid, the concentration of hydrogen ions in the solution is equal to the acid concentration, which is 0.32 M. To find the [OH−], we use the water dissociation constant (Kw) which is 1.0 × 10−14 at 25 °C. The ion product of water is given by Kw = [H+][OH−], so we calculate [OH−] as:
[OH−] = Kw / [H+] = 1.0 × 10−14 / 0.32 = 3.125 × 10−13 M
The pH can be calculated using the formula pH = -log[H+], giving us:
pH = -log(0.32) ≈ 0.50
Therefore, the hydroxide ion concentration in a 0.32 M HCl solution is approximately 3.125 × 10−13 M and the pH of the solution is about 0.50.