You dissolve 0.476 g of naoh in 2.00 l of a buffer solution that originally had [h2po4-] = [hpo42-]= 0.132 m. look up the ka value in your text. a. what is the ph of the buffer solution before addition of the sodium hydroxide? ph = b. what is the concentration of dihydrogen phosphate after addition of the sodium hydroxide? [h2po4-] = m c. what is the concentration of the hydrogen phosphate after addition of the sodium hydroxide? [hpo42-] = m d. what is the ph of the buffer solution after addition of the sodium hydroxide? ph =