Question

O ACIDS AND BASES Calculating the composition of a buffer of a given pH A chemistry graduate student is given 500 ml of a 0.40 M trimethylamine (CH) N) solution. Trimethylamine is a weak base with K = 7,410 . What mass of (CH) NHCI should the student dissolve in the (CH) N solution to turn it into a buffer with pH = 11.12? You may assume that the volume of the solution doesn't change when the (CH) NHCl is dissolved in it. Be sure your answer has a unit symbol, and round it to 2 significant digits

Answer 1

Date: 1 POH = pke + log [BH] [B] pH = 11.12 pH + poh. 14 poh - 14-11.12 2.88 pkb = -log (ko) = -log (7.4 X 15 4 ) = 3 Bas) = 0.40m = 3.13 + log [BHT] - log (0.40] 2.88 = 3.13 + log LBH" } -(-0.35) 2.88 - 3.13 - 0.39. log (81H+ ) -0.64 = log (BH" } [[BH] = 0.22M Molosity. masa tume (in liter) 0.22 = x tooo mass x 95-57 L 500 mass = 10.51 g बेटी बचाओ बेटी पढ़ाओ