hydrofluoric acid is used to etch class and as a precursor in the production of prozac. it exists in aqueous solution and has a molar mass of 20.01 g/mol. Achemist dissolves a 0.2001 g sample in 20.0 nL and titrates it with 0.400 M NaOH. What is the pH at the equivalence point? what is the pH at the 10.0 mL base added? what is the pH at the 30.0 mL base added?