Thermal Physics

Question 1

Definition of internal energy of a substance

Answer 1

Sum of randomly distributed kinetic and potential energies of the molecules in a substance

Question 2

Definition of the potential energy of a molecule

Answer 2

The energies that particles have due to the electrostatic attraction that exists with other particles (in a non-ideal gas)

Question 3

Why is potential energy of a molecule always negative?

Answer 3

Energy must be supplied to break the atomic/molecular bonds

Question 4

What is potential energy defined to be in a gas?

Answer 4

0

Question 5

Why is potential energy 0 in a gas?

Answer 5

There are negligible electrostatic forces between the atoms

Question 6

Describe potential energy in a liquid

Answer 6

Has a negative value due to the electrostatic forces that need energy to be broken.

Question 7

Describe potential energy in a solid

Answer 7

The electrostatic forces between atoms are very large, giving the potential energy a large negative value

Question 8

What is specific latent hear

Answer 8

The energy needed to change the state of 1kg of a substance