Calculate the pH of 1.28×10−3 M KOH.
thanks.
OH^- = 1.28E-3
Then pOH = 2.89 and
pH + pOH = pKw = 14
pH = 14-2.89 = 11.11
1.28×10^−3
What is the pH of a 5.91 x 10-3 M solution of HCl?
To calculate the pH of a solution, we need to determine the concentration of hydrogen ions (H+) in the solution. For a strong base like KOH, it dissociates completely into its constituent ions, K+ and OH-. Since the hydroxide ion (OH-) is responsible for basicity, we can find the concentration of OH- ions in the solution.
In the given problem, the concentration of KOH is 1.28×10−3 M. Since KOH dissociates completely, the concentration of OH- ions will also be 1.28×10−3 M.
To find the pOH, we can use the formula:
pOH = -log[OH-]
pOH = -log(1.28×10−3)
pOH ≈ 2.89
Since the sum of pH and pOH in any solution is always equal to 14 at 25°C, we can find the pH using the equation:
pH = 14 - pOH
pH = 14 - 2.89
pH ≈ 11.11
Therefore, the calculated pH of 1.28×10−3 M KOH is approximately 11.11.