Question
Wed January 02, 2013 By: Nitin Gupta

what is specific heat? how are cp and cv calculated?

Expert Reply
Wed January 02, 2013
The specific heat is the amount of heat per unit mass required to raise the temperature of the substance by one degree Celsius. The relationship between heat and change in temperature is usually expressed in the form shown below where c is the specific heat.

In simple words, The amount of heat needed to raise the temperature of one gram of a substance by one degree Celsius is specific heat.

For Monoatomic gases

No of degrees are 3.All Three are translational energies

Hence the total internal energy for 1 mole of gas is

U=(1/3KBT+. 1/3KBT+1/3KBT)NA (Acc to law of equipartition law)(K=boltzman constant)

U=3/2KBTNA

diff. it both sides w.r.t. T

=dU/dT=3/2R (R=KBNA)

but dU/dT=Cv

therefore Cv =3/2R

hence Cp=CV+R

Cp=3/2R+R

CP=5/2R

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