1. Earlier you learned that carbonate, CO32-(aq), is a component of soil and can neutralize acid deposition. Given what you have learned about acid-base reactions and pH curves, sketch the pH curve for soil containing carbonate ions that undergos continual addition of hydronium ions from acid deposition. Include relevant chemical equations and information that explain the aspects of the pH curve you sketch.
2. a. Complete the ICE table for a solution of nitrous acid, HNO2(aq), one of the acids associated with acid deposition.
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Concentration
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HNO2(aq)
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H3O+(aq)
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NO2-(aq)
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Initial (mol/L)
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0.045
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Change (mol/L)
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Equilibrium (mol/L)
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0.0043
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b. Calculate the pH of the nitrous acid solution.
3. The Kb for ammonia is 1.8 x 10-5.
a. Use a chemical reaction to explain how aqueous ammonia can create a basic solution.
b. Calculate the hydroxide ion concentration and the pH of a 0.125 mol/L ammonia solution.
4. The equilibrium concentration for a weak monoprotic acid is 0.075 mol/L. The measured pH is 6.25. Calculate the Ka for this acid.
5. The pH of a 0.002 50 mol/L solution of benzoic acid is 3.65. Calculate the Ka for benzoic acid. (Hint - This question does not state that the given concentration is an equilibrium concentration.)