Question

Prove that internal energy is a thermodynamic property

Answer 1

Internal energy of a system depends on the temperature of the system.
As we know that internal energy is the sum of all the K.E+P.E+V.E etc.
When the temperature is increased the molecules of the system gain energy and start moving with high speed (their K.E increases) ,they collide with each other as a result the internal energy of the system increases.
Similarly when the temperature is decreased, the K.E of the molecules decreases due to which internal energy also decreases.