Kinetic energy and heat energy of molecule?

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Hardik Batra
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I know that .
Average kinetic energy of a molecule is (f/2)kT (for translational motion.where f=3 )

In my textbook given that...

If the degree of freedom of the gas molecule is f then the average heat energy of each molecule of the gas is = E(avg.) = (f/2)kT

which is same as the average kinetic energy.

Are the avg. kinetic energy and heat energy both are same or there is difference between them?
 
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I think the textbook may just be using slightly sloppy language, using "heat energy" for what should be "kinetic energy". As heat is not a state function, there is no "heat energy" function that can be associated with an equation of state. Heat is energy flow into or out of a system that is not work.
 
Thermal energy might have been a better choice of words.
 
256bits said:
Thermal energy might have been a better choice of words.

thermal Energy and kinetic energy of molecule is same?
 
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Hardik Batra said:
thermal Energy and kinetic energy of molecule is same?

It depends on the definitions. I would prefer simply the phrase "total energy" of the material. For an ideal (perfect) gas the total energy is the same as the kinetic energy of the molecules, for a non-perfect gas, there can be potential energy contributions to the total energy.

Thermal energy is often just another word for "heat".