Calorimetry: Question #3 Octane, C8H18 , is a constituent of gasoline, and burns in the presence of oxygen to produce water and carbon dioxide: AH°rxn 2 C3H18 (1) + 25 O2(g) → 16 CO2(g) + 18 H2O1) E3H18 (1) _kJ/2mol When a 1.00-gram sample of octane is burned in a bomb calorimeter the temperature of the water and the calorimeter rises from 25.00°C to 33.20°C. If the heat capacity, Cbomb cal, of the empty bomb calorimeter is 837 J/°C, and the mass of the water is 1.200 kg: a) Calculate the heat, q, transferred, during the combustion, to the calorimeter: 6.86 kJ (calorimter) + qbomb cal Cbomb cal .ΔΤ b) Calculate the heat, q, transferred, during the combustion, to the water: 41.2 kJ (1.200 kg H20) + 9H2O = + mH20 • AT • SH20 c) Calculate the enthalpy change (AHºxr Prxn= kJ/2mol) for this reaction (2 mol of C3H18 (1): [ Select ] kJ/2 mol C3H18 (1)

Calorimetry: Question #3 Octane, C8H18 , is a constituent of gasoline, and burns in the presence of oxygen to produce water and carbon dioxide: AH°rxn 2 C3H18 (1) + 25 O2(g) → 16 CO2(g) + 18 H2O1) E3H18 (1) _kJ/2mol When a 1.00-gram sample of octane is burned in a bomb calorimeter the temperature of the water and the calorimeter rises from 25.00°C to 33.20°C. If the heat capacity, Cbomb cal, of the empty bomb calorimeter is 837 J/°C, and the mass of the water is 1.200 kg: a) Calculate the heat, q, transferred, during the combustion, to the calorimeter: 6.86 kJ (calorimter) + qbomb cal Cbomb cal .ΔΤ b) Calculate the heat, q, transferred, during the combustion, to the water: 41.2 kJ (1.200 kg H20) + 9H2O = + mH20 • AT • SH20 c) Calculate the enthalpy change (AHºxr Prxn= kJ/2mol) for this reaction (2 mol of C3H18 (1): [ Select ] kJ/2 mol C3H18 (1)

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter6: Thermochemistry

Section: Chapter Questions

Problem 105AE: Combustion of table sugar produces CO2(g) and H2O( l). When 1.46 g table sugar is combusted in a...

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