Final answer:
To find the pH of a 0.580 M KCH3CO2 solution at 25°C, we need to determine the concentration of H3O+ ions. We can use the dissociation equilibrium equation for acetic acid and the Ka to calculate the concentration of H3O+ ions. After finding the concentration, we can plug it into the pH equation to determine the pH of the solution.
Step-by-step explanation:
The pH of a solution can be calculated using the equation pH = -log[H3O+]. To find the pH of a 0.580 M KCH3CO2 solution at 25°C, we need to determine the concentration of H3O+ ions. KCH3CO2 is a salt formed by the reaction of potassium hydroxide (KOH) and acetic acid (CH3CO2H). In water, KCH3CO2 dissociates to form K+ and CH3CO2- ions. Since acetic acid is a weak acid, it only partially dissociates into H3O+ and CH3CO2- ions. Therefore, we need to consider the dissociation of acetic acid to calculate the concentration of H3O+ ions in the solution.
Using the dissociation equilibrium equation for acetic acid: CH3CO2H(aq) + H2O(l) ⇌ CH3CO2-(aq) + H3O+(aq)
We can use the Ka of acetic acid and its initial concentration to calculate the concentration of H3O+ ions and then find the pH using the equation pH = -log[H3O+]. In this case, we have the Ka for formic acid, so we can use a similar method to calculate the pH of the KCH3CO2 solution.
After calculating the concentration of H3O+ ions, plug the value into the equation pH = -log[H3O+] to find the pH of the solution.