Question

When you squeeze lemon juice or lime juice on an avocado to keep it from turning brown you are using the preservative power of citric acid. Citric acid, H3C6H507, is a polyprotic acid, which is widely used a preservative as well as a flavoring agent. Kal = 7.4 x 10-4, Ka2 = 1.7 x 10-5, and Ka3 = 4.0 x 10-7 In a 0.200 M solution of NaH2C6H507 (sodium dihydrogen citrate), what is your primary citrate containing species in solution? Enter the chemical formula ; In your entry simply type letters and numbers ignoring upper or lower case as well as super or subscripts. Don't forget the charge! Calculate the pH of the solution assuming that it is dominated by the properties of you primary species. pH =

Answer 1

chemical formula = H₂CGH SOF concentration F = 0.200M CH+] = ki kz F + Kikw KITE = 7.4x16 4x1-7x105x0.200 + 7.4x104xiol4 7.4x104 + 0.200 (+4) = 1:1195x1644 pH = -log (112x164) pH = 3.95