Calculate the pH of 30.0 mL of 0.025 M NaOH
To calculate the pH of a solution of NaOH, we need to know the concentration of the hydroxide ion (OH-) in the solution. When NaOH dissolves in water, it completely dissociates into Na+ and OH- ions. Since NaOH is a strong base, its concentration is equal to the concentration of OH- ions.
Given that the concentration of NaOH is 0.025 M, the concentration of OH- ions is also 0.025 M.
To calculate the pH of a basic solution, we can use the equation for the pOH:
pOH = -log[OH-]
First, let's calculate the pOH:
pOH = -log(0.025) = 1.60
Next, we can use the relationship between pH and pOH:
pH + pOH = 14
Solving for pH:
pH = 14 - pOH = 14 - 1.60 = 12.40
Therefore, the pH of 30.0 mL of 0.025 M NaOH is 12.40.