Heat Capacity: Difference between revisions

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==References==
==References==
==Heat Capacity==
The concept of Heat Capacity is integral to understanding how the temperature of a substance rises and falls. Heat Capacity is the ratio of energy added or removed from a substance to the temperature change observed in that substance. Typically, heat capacities are expressed in terms of the amount of heat (kJ, J, or kCal) that needs to be added to raise the temperature of a substance by 1 degree (Celsius, Fahrenheit, Kelvin). Typical units of Heat Capacities are J/g, kJ/kg, and BTU/lb-mass. The SI unit of heat capacity is J/g.


==Calculating/Estimating Heat Capacities==
==Calculating/Estimating Heat Capacities==

Revision as of 14:52, 31 July 2019

Main Idea

Mathematical Model

Computational Model

Examples

Simple

Middling

Difficult

Connectedness

History

See also

Further reading

External links

References

Calculating/Estimating Heat Capacities

Kopp's Rule

Applications

Examples

Problem: You have a burner that emits 15,000 J of heat in the period that it is left on. Will this burner be able to raise 2 kg of water from 50 °C to 52 °C? The specific heat capacity of water is 4,186 J/kg °C.

Solution: Use Q=mCΔT. The amount of heat needed to do the process specified in the question is Q=(2 kg)*(4,186 J/kg °C)*(2 °C)=16,744 J. Since the burner only gives of 15,000 J, the water will not reach the desired temperature.

Problem: What is the specific heat of 3 g substance that takes 100 J to raise 3 degrees.

Solution: Use Q=mCΔT. Q=100 J, m= 3 g, ΔT=3 °C. 100J= (3 g)*(C)*(3 °C). C=11.11111 J/g °C.

History

See also

Further reading

Elementary Principles of Chemical Processes (3rd Edition) By: Richard M. Felder & Ronald M. Rousseau

Encyclopædia Britannica, 2015, "Heat capacity"

References