The combustion of wood produces an average of 15 000 kJ/kg. Suppose 4.30 kg of wood is burned in a fireplace that circulates heat around a house containing 800.0 kg of air (Cair = 1.02 kJ/kg°C), increasing the average air temperature of the house from 18°C to 23°C. a. What percentage of the wood's energy went directly into heating the air? (3) b. Brick (in addition to being non-flammable) has a high specific heat capacity. Why does it make sense in terms of energy efficiency to surround fireplaces with brick? (2)

The combustion of wood produces an average of 15 000 kJ/kg. Suppose 4.30 kg of wood is burned in a fireplace that circulates heat around a house containing 800.0 kg of air (Cair = 1.02 kJ/kg°C), increasing the average air temperature of the house from 18°C to 23°C. a. What percentage of the wood's energy went directly into heating the air? (3) b. Brick (in addition to being non-flammable) has a high specific heat capacity. Why does it make sense in terms of energy efficiency to surround fireplaces with brick? (2)

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

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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Answer #3
1. How many joules of energy would be required to raise the temperature of 3.2 grams of mercury 4.2°C? The specific heat of mercury is 0.14 J/(g.°C).
MN.19.
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