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The following questions test your understanding of Bronsted-Lowry acids and bases, the application of thermodynamics to an acid-base equilibrium and a pH calculation for a weak acid and salt of a weak acid

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The following questions test your understanding of Bronsted-Lowry acids and bases, the application of thermodynamics to an acid-base equilibrium and a pH calculation for a weak acid and salt of a weak acid. Q1. For each of the following reactions identify the Bronsted-Lowry acids and bases and the conjugate acid-base pairs. 1. H,PO (aq) + H20(1) - H3O+ (aq) + HPO3 -(aq) 2. H,SO, (aq) + CH,CH, OH(aq) -HSO (aq) + CH, CH, OH2 (aq) 3. NH, (aq) + CH, COOH(aq) = NH2 (aq) + CH, COOH, (aq) Example: CN-(aq) + H20(1) - OH-(aq) + HCN(aq) Acid: H, O Base: CN- Conjugate acid/base pairs : CN-/HCN and H, O/OH Q2. The Kb of methylamine, CH, NH,, is 4.4 x 10-4 at 25. C. 1. Write the equation for the hydroylsis of methylamine in water. 2. Calculate the value of A Go for this reaction. 3. What is the value of A G when [H, 0+]=6 . 7 x 10-9 M, [CH, NH; ]=2 . 4 x 10 - M and [CH, NH,]=9 . 8 x 10 -2 M? Is the reaction spontaneous in the forward direction under these conditions? Justify your answer. Q3. Hypochlorous acid, HOCI, is a weak acid and extensively used as a bleaching agent. Its acidity constant, Ka, is 3.2 x 10-8. Calculate 1. the pH of a 0.650M HOCI solution 2. the pH of a 0.040M NaOCI solution.