CHM 1046 Exam 3 Study Guide Questions With Correct Verified Answers

According to the Arrhenius concept, an acid is a substance that __________ - correct answers causes an increase in the concentration of H+ in aqueous solutions A Bronsted-Lowry base is defined as a substance that __________. - correct answers acts as a proton acceptor What is the conjugate acid of NH3? - correct answers NH₄⁺ What is the pH of an aqueous solution at 25°C in which [H+] is 0.025 M? - correct answers 1.60 What is the pH of an aqueous solution at 25°C in which [OH-] is 0.025 M? - correct answers 12.4 What is the pH of an aqueous solution at 25° that contains 3.98 × 10-9 M hydronium ion? - correct answers 8.400 What is the concentration (in M) of hydroxide ions in a solution at 25°C with pH = 4.282? - correct answers 1.91 × 10^-10 What is the pH of a 0.015-M aqueous solution of barium hydroxide (BaOH2)? - correct answers 12.48 Nitric acid is a strong acid. This means that __________. - correct answers HNO3 dissociates completely to H+(aq) and NO3-(aq) when it dissolves in water Of the following acids, __________ is not a strong acid. - correct answers HNO₂ Of the acids in the table below, __________ is the strongest acid. Acid | Ka HOAc 1.8 × 10-5 HCHO2 1.8 × 10-4 HClO 3.0 × 10-8 HF 6.8 × 10-4 - correct answers HF The pH of a 0.55-M aqueous solution of hypobromous acid, HBrO, at 25°C is 4.48. What is the value of Ka for HBrO? - correct answers 2.0 × 10^-9 The Ka of hypochlorous acid (HClO) is 3.0 × 10-8 at 25°C. Calculate the pH of a 0.0385-M hypochlorous acid solution. - correct answers 4.47 The acid-dissociation constant, Ka, for gallic acid is 4.57 × 10-3. What is the base-dissociation constant, Kb, for the gallate ion? - correct answers 2.19 × 10^-12 Of the following, which is the strongest acid? - correct answers HIO4 The pH of a solution that contains 0.818 M acetic acid (Ka = 1.76 x 10-5) and 0.172 M sodium acetate is - correct answers 4.077 Of the following solutions, which has the greatest buffering capacity? - correct answers 0.821 M HF and 0.909 M NaF A 25.00-mL sample of 0.723 M HClO4 is titrated with a 0.273 M KOH solution. The H3O+ concentration after the addition of 10.0 mL of KOH is __________ M. - correct answers 0.440 The pH of a solution prepared by mixing 45 mL of 0.183 M KOH and 65 mL of 0.145 M HCl is __________. - correct answers 1.97 The pH of a solution prepared by mixing 50.0 mL of 0.125 M KOH and 50.0 mL of 0.125 M HCl is __________. - correct answers 7.00 A 25.0-mL sample of a solution of an unknown compound is titrated with a 0.115 M NaOH solution. The titration curve above was obtained. The unknown compound is __________. - correct answers a weak acid The solubility of lead (II) chloride (PbCl2) is 1.6 x 10-2 M. What is the Ksp of PbCl₂? - correct answers 1.6 x 10^-5 Calculate the molar solubility of MX2,