A 25.0 mL sample of 0.200 M benzoic acid, C H COOH ( )
CHEMISTRY · Multi-part · A Level · Chemistry · Acids and bases · Acids and bases
Problem
A 25.0 mL sample of 0.200 M benzoic acid, C6H5COOH (Ka=6.3×10−5), is titrated with 0.300 M NaOH. A total of 45.0 mL of the base has been added.
Provide complete, justified calculations for each of the following.
(a) Determine which reactant is present in excess after the 45.0 mL addition, and calculate the number of moles of that excess species.
(b) Calculate the molar concentration of hydroxide ion in the final reaction mixture.
(c) Compute the numerical values of the pOH and the pH of the solution, reporting both to two significant figures.