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Saccharin, C7H4NSO3H, is a weak acid
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- The base ethylamine (CH3CH2NH2) has a Kb of. A closely related base, ethanolamine(HOCH2CH2NH2), has a Kb of 3.2105. (a) Which of the two bases is stronger? (b) Calculate the pH of a 0.10M solution of the strong base?arrow_forwardBarbituric acid, HC4H3N2O3, is used to prepare barbiturates, a class of drugs used as sedatives. A 325-mL aqueous solution of barbituric acid has a pH of 2.34 and contains 9.00 g of the acid. What is Ka for barbituric acid?arrow_forwardWrite an equation for each of the following buffering actions. a. the response of a HPO42/PO43 buffer to the addition of OH ions b. the response of a HF/F buffer to the addition of OH ions c. the response of a HCN/CN buffer to the addition of H3O+ ions d. the response of a H3PO4/H2PO4 buffer to the addition of H3O+ ionsarrow_forward
- Consider pyridine, C5H5N, a pesticide and deer repellent. Its conjugate acid, C5H5NH+, has K a =6.7106. (a) Write a balanced net ionic equation for the reaction that shows the basicity of aqueous solutions of pyridine. (b) Calculate Kb for the reaction in (a). (c) Find the pH of a solution prepared by mixing 2.74 g of pyridine in enough water to make 685 mL of solution.arrow_forwardA solution of acetic acid, HC2H3O2, on a laboratory shelf was of undetermined concentration. If the pH of the solution was found to be 2.57, what was the concentration of the acetic acid? The Ka of acetic acid is 1.7 105.arrow_forwardMethylammonium chloride is a salt of methylamine, CH3NH2. A 0.10 M solution of this salt has a pH of 5.82. a Calculate the value for the equilibrium constant for the reaction CH3NH3++H2OCH3NH2+H3O+ b What is the Kb value for methylamine? c What is the pH of a solution in which 0.450 mol of solid methylammonium chloride is added to 1.00 L of a 0.250 M solution of methylamine? Assume no volume change.arrow_forward
- Tartaric acid is a weak diprotic fruit acid with Ka1 = 1.0 103 and Ka2 = 4.6 105. a Letting the symbol H2A represent tartaric acid, write the chemical equations that represent Ka1 and Ka2. Write the chemical equation that represents Ka1 Ka2. b Qualitatively describe the relative concentrations of H2A, HA, A2, and H3O+ in a solution that is about 0.5 M in tartaric acid. c Calculate the pH of a 0 0250 M tartaric acid solution and the equilibrium concentration of [H2A]. d What is the A2 concentration in solutions b and c?arrow_forwardConsider sodium acrylate, NaC3H3O2. Ka for acrylic acid (its conjugate acid) is 5.5 105. (a) Write a balanced net ionic equation for the reaction that makes aqueous solutions of sodium acrylate basic. (b) Calculate Kb for the reaction in (a). (c) Find the pH of a solution prepared by dissolving 1.61 g NaC3H3O2 in enough water to make 835 mL of solution.arrow_forwardCalculate the mass in grams of ammonium chloride, NH4C1, that would have to be added to 500. mL of 0.10-M NH3 solution to have a pH of 9.00.arrow_forward
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