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| 1 . |
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How many moles of sodium hypobromite, NaBrO, should be added to 1.00 L of 0.200 M hypobromous acid, HBrO (Ka = 2.5 x 10-9), to form a buffer solution of pH 8.80? Assume that no volume change occurs when the NaBrO is added. Online Text [Hint]
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| 2 . |
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You need to make a buffer with a pH of 3.50 from citric acid and sodium dihydrogen citrate. If you ignore all higher ionizations of the dihydrogen citrate ion, what concentration of sodium dihydrogen citrate needs to be added to 0.40 M acid (Ka = 7.4 x 10-4)? Online Text [Hint]
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| 3 . |
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What is the final pH if 0.020 mol HCl is added to 0.500 L of a 0.28 M NH3 and 0.22 M NH4Cl buffer solution (Kb (NH3) = 1.8 x 10-5)? Online Text [Hint]
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| 4 . |
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A buffer contains 0.30 M acetic acid and 0.20 M sodium acetate. What is the pH of the buffer as prepared and after 0.030 mol/L of a strong acid or 0.030 mol/L of a strong base are added (Ka = 1.8 x 10-5)? Online Text [Hint]
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| 5 . |
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Determine the pH of a solution prepared by mixing 45 mL of 0.183 M KOH with 65 mL of 0.145 M HCl. Online Text [Hint]
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| 6 . |
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A 50.0-mL sample of 0.50M acetic acid, HC2H3O2, is titrated with a 0.150 M NaOH solution. Calculate the pH after 25.0 mL of the base have been added (Ka = 1.8 x 10-5). Online Text [Hint]
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| 7 . |
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Estimate the pH at the equivalence point of an HOAc solution if 25.5 mL of this solution required 37.5 mL of 0.175 M NaOH to reach the equivalence point (Ka = 1.8 x 10-5). Online Text [Hint]
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| 8 . |
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Calculate the pH of a solution formed by adding 50.0 mL of 6.0 M NH3 to 75.0 mL of 1.0 M HCl. (Kb (NH3) = 1.8 x 10-5). Online Text [Hint]
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| 9 . |
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An initial pH of 1.00, an equivalence point at pH 7.0, and a relatively long, nearly vertical middle section correspond to a titration curve for Online Text [Hint]
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| 10 . |
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Consider the diagram of a potentiometric titration curve shown below.  Which of the following indicators would be the best one to use for this titration? | Indicator | pKa |
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| methyl red | 5.3 | | bromthymol blue | 6.8 | | thymol blue | 8.8 | | phenolphthalein | 9.1 | Online Text [Hint]
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| 11 . |
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Which of the following statements is not a proper comparison of the titration curves of acid samples with different Ka values? Online Text [Hint]
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| 12 . |
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At what point in this titration of arsenic acid (H3AsO4) with base would one expect to find a mixture of primarily H2AsO4- and a lesser amount of HAsO42-?
 Online Text [Hint]
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