ii). 6 iii). 10? c). The mercuric ion, Hg2+, has a high affinity for chloride: Hg2+ + 4Cl– HgCl42–, Cl  for which the formation constant is = 3.98 1015. For a solution containing  0.5 mol L-1 total chloride and 5.00 10-3 mol L-1 total EDTA, determine the fraction of Hg existing as the free ion, as the tetrachloride anion, and as the EDTA complex, at a pH of i). 2 ii). 6 iii). 10 [You should assume that the total metal ion concentration is much less than 0.05 mol L-1.] d). An amalgam is known to contain only mercury, sodium, and calcium. 5.218 grams of the sample is treated with an appropriate oxidizing agent, and made up to 500 mL. 25 mL aliquots of this solution, buffered to pH = 2.6, are titrated against a 0.0122 mol L-1 MgY2– solution: the mean titre value obtained is 44.19 mol L-1. When 10 mL aliquots are buffered to a pH of 9.5, a titre value of 57.43 mol L-1 is obtained. Determine the percentage by mass of the mercury, sodium, and calcium in the amalgam. PROBLEM 22. Greenhouse gas emissions are a topic of global environmental concern. The increase in atmospheric concentration of one greenhouse gas, CO2, has been over the past several decades. a). Let us approximate the distribution of greenhouse gases in the Earth's atmosphere by assuming that these gases (CO2, H2O vapour etc) are localized within a layer between the altitudes of 10 and 11 km. [Such a description is not accurate, but serves to illustrate some concepts.] What is the effect of such a greenhouse-gas layer upon the temperature of the atmosphere at an altitude of 5 km? b). What is the layer's effect on atmospheric temperature at 15 km? Explain, qualitatively, this 'side-effect' of the Greenhouse layer. c). How does temperature change in the lower atmosphere influence the equilibria of CO2 and of H2O between the gaseous and aqueous phases? Will a shift in the
ii). 6 iii). 10? c). The mercuric ion, Hg2+, has a high affinity for chloride: Hg2+ + 4Cl– HgCl42–, for which the formation constant is Cl = 3.98  1015. For a solution containing 0.5 mol L-1 total chloride and 5.00  10-3 mol L-1 total EDTA, determine the fraction of Hg existing as the free ion, as the tetrachloride anion, and as the EDTA complex, at a pH of i). 2 ii). 6 iii). 10 [You should assume that the total metal ion concentration is much less than 0.05 mol L-1.] d). An amalgam is known to contain only mercury, sodium, and calcium. 5.218 grams of the sample is treated with an appropriate oxidizing agent, and made up to 500 mL. 25 mL aliquots of this solution, buffered to pH = 2.6, are titrated against a 0.0122 mol L-1 MgY2– solution: the mean titre value obtained is 44.19 mol L-1. When 10 mL aliquots are buffered to a pH of 9.5, a titre value of 57.43 mol L-1 is obtained. Determine the percentage by mass of the mercury, sodium, and calcium in the amalgam. PROBLEM 22. Greenhouse gas emissions are a topic of global environmental concern. The increase in atmospheric concentration of one greenhouse gas, CO2, has been over the past several decades. a). Let us approximate the distribution of greenhouse gases in the Earth's atmosphere by assuming that these gases (CO2, H2O vapour etc) are localized within a layer between the altitudes of 10 and 11 km. [Such a description is not accurate, but serves to illustrate some concepts.] What is the effect of such a greenhouse-gas layer upon the temperature of the atmosphere at an altitude of 5 km? b). What is the layer's effect on atmospheric temperature at 15 km? Explain, qualitatively, this 'side-effect' of the Greenhouse layer. c). How does temperature change in the lower atmosphere influence the equilibria of CO2 and of H2O between the gaseous and aqueous phases? Will a shift in the
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