To determine the pH of a 0.1 M KOH solution, let's go through the problem step-by-step.
1. Identify the nature of the solute:
Potassium hydroxide (KOH) is a strong base which completely dissociates in water. This means that for every mole of KOH dissolved, it produces one mole of hydroxide ions (OH⁻).
2. Determine the concentration of hydroxide ions (OH⁻):
Since the concentration of the KOH solution is 0.1 M and it fully dissociates in water, the concentration of hydroxide ions (OH⁻) will also be 0.1 M.
3. Calculate the pOH of the solution:
The pOH is calculated using the formula:
[tex]\[
\text{pOH} = -\log[\text{OH}^-]
\][/tex]
Plugging in the concentration of hydroxide ions:
[tex]\[
\text{pOH} = -\log[0.1] = 1.0
\][/tex]
4. Determine the pH using the relationship between pH and pOH:
The relationship between pH and pOH is given by:
[tex]\[
\text{pH} + \text{pOH} = 14
\][/tex]
Knowing the pOH is 1.0, we can find the pH:
[tex]\[
\text{pH} = 14 - \text{pOH} = 14 - 1.0 = 13.0
\][/tex]
Therefore, the pH of a 0.1 M KOH solution is 13.0.