What are the pOH and pH of a 0.0125M solution of potassium KOH
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To determine the pOH and pH of a solution of potassium hydroxide (KOH), we need to first understand the properties of this compound.
KOH is a strong base, meaning it dissociates completely in water to produce hydroxide ions (OH-) and potassium ions (K+). Knowing this, we can calculate the concentration of OH- ions in the solution by considering the molarity of KOH.
Given that the molarity (M) of the KOH solution is 0.0125M, we can assume that the concentration of hydroxide ions (OH-) in the solution is also 0.0125M.
Now, the pOH is defined as the negative logarithm (base 10) of the hydroxide ion concentration. Thus, we can calculate the pOH using the following formula:
pOH = -log[OH-]
Substituting the value of [OH-] into the formula, we get:
pOH = -log(0.0125)
Calculating this, we find that the pOH of the 0.0125M KOH solution is approximately 1.9.
To determine the pH of the solution, we need to remember that pH is calculated using the following formula:
pH = 14 - pOH
Substituting the pOH value we obtained earlier, we have:
pH = 14 - 1.9
Calculating this, we find that the pH of the 0.0125M KOH solution is approximately 12.1.
So, to summarize:
- The pOH of the 0.0125M KOH solution is approximately 1.9.
- The pH of the 0.0125M KOH solution is approximately 12.1.
To find the pOH and pH of a solution, we need to know the hydroxide ion concentration (OH-) of the solution.
Given that the solution is 0.0125M potassium hydroxide (KOH), let's assume it fully dissociates to produce equal amounts of potassium cation (K+) and hydroxide anion (OH-). Therefore, the concentration of hydroxide ions (OH-) in the solution is also 0.0125M.
To calculate pOH, we can use the following equation:
pOH = -log[OH-]
Substituting the value of [OH-]:
pOH = -log(0.0125)
Using a calculator:
pOH ≈ 1.903
Now, to find the pH, we can utilize the equation:
pH + pOH = 14
Rearranging the equation:
pH = 14 - pOH
Substituting the value of pOH:
pH = 14 - 1.903
Using a calculator:
pH ≈ 12.097
Therefore, the pOH of the 0.0125M solution of potassium hydroxide (KOH) is approximately 1.903, and the pH is approximately 12.097.