Question

How much HCl must be added to a liter of buffer that is 1.5 M in acetic acid and 0.80 M in sodium acetate to result in a buffer pH of 3.80?

Answer 1

4486 pka for acetic and = 4.76 Concentration of sodium acetate [Ac] =0.80m. concentration of acetic and [le Ac] = 1.5m pk = 4-76 + log(s) = To lower the pre to 3-80 as given in the problem ratio of [Ac ] must be [HA 3.80 = 4.76+ log in 1 [n Ac [AC 20.1096 [+Ac Since, rece is added to the solution of Aă and HAC moles of AŘ will decrease and HAC will increase set & moles of Au will be consumed and moles of HAC Produceed. 0-80-x = 0.1096 1.5tr o. 1644+ 0.1096x = 0.80 - se 1.10963 = 0-6356 x = 0.57 moles m 0.57 moles of rece oncest be added to a liter of Buffer that is 1.5m in acetic and and o.som en sodium acetate to result in a beeffer pH of 3.80.