5- Ascorbic acid (molecular weight = 176.12) is too acidic toadminister by the parenteral route. The acidity of ascorbic acid ispartially neutralized by adding a basic compound, usually sodiumcarbonate or sodium bicarbonate. Thus, the injectable productcontains sodium ascorbate, ascorbic acid and the neutralizingagent.
a. What is the pH of an injectable solution containing onlyascorbic acid in the concentration of 55 g per liter of solution(Ka1 = 5 x 10-5 and Ka2 = 1.6 x 10-12).
b. What is the molar ratio of sodium ascorbate to ascorbic acidand the percentage required to prepare an injectable solution witha pH of 5.77?
