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5 Thermochemistry Solutions to Exercises Solve. 1.0 kW = 1.0 kJ/s = 1.0kJ 60 min = 3.6x10³ kJ m² m² m² min 1hr m² hr 5645 kJ X 1 mol sucrose 0.20 sucrose = 3.298 = kJ/m - hr mol sucrose 342.3 g sucrose m² hr for sucrose production 3.298 kJ for sucrose X 100 = 0.092% sunlight used to produce sucrose 3.6x10³ kJ total solar 5.111 (a) C₆H₁₂O₆(s) + (g), = 2803 kJ This is the reverse of the combustion of glucose (Section 5.8 and Solution 5.89), so = -(-2803) kJ = +2803 kJ. 5.5 10¹⁶ yr X 1 mol CO₂ CO₂ X 6 mol kJ = 5.838 X 10¹⁷ = 5.8x10¹⁷ kJ (b) 5.838 X yr 10¹⁷ kJ 1000] kJ 365 1 yr d 24 1d hr 60 1hr min 1min 1W-s J 1MW 1.9x10⁷ MW 10³ 1 plant = = 19,000 nuclear power plants MW Integrative Exercises 5.112 (a) = -393.5 kJ + 2(-285.83 (-74.8 2(0) = -890.36 = -890.4 kJ/mol CH₄ -890.36 1 mol mol CH₄ 1kJ 6.022 molecules CH₄ = 10⁻¹⁸ = 1.479 X 10⁻¹⁸ J/molecule (b) 8 keV X 1000 1 keV 96.485 eV - mol 6.022 X kJ = = J/X-ray The X-ray has approximately 1000 times more energy than is produced by the combustion of 1 molecule of CH₄(g). 5.113 Ag(s) + = -278.5 kJ 105.90 135