CHEM 112 Lecture Notes - Lecture 20: Ammonium Carbonate, Ion, Sodium Acetate
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Chem112 lecture 20 ka and kb. Which of the following is not a conjugate base of a strong acid: cl-, f-, no3, the answer is f- Determining equilibrium constant in various acid/base reactions: methylamine (ch3nh2) is a weak base. If the ph of a 0. 065 m solution of the amine is 11. 70, what is the value of kb: ch3nh2 + h2o oh- + ch3nh3, poh = 14 ph = 2. 3 [oh-]eq = 0. 005m. Estimating ph of an aqueous, weak acid solution: what is the ph of a 0. 02m solution of benzoic acid, the ka for this acid is 6. 3 x 10-5, c6h5cooh + h2o c6h5coo- + h3o+ X is so small that the equilibrium concentration of acid is essentially equal to the initial concentrations: so thus, ka = = 5. 6 x 10 10 : x = 3. 35 x 10-6 = [oh-, poh = -log [oh-] = -log [3. 35 x 10-6] = 5. 47, ph = 14 5. 47 = 8. 53.
