Question

What happens to a sheet of copper as the average kinetic energy of the copper molecules decreases?

A. It melts.
B. It expands.**
C. It gets cooler.
D. It gains energy.

Answer 1

It gets cooler.

Step-by-step explanation:

I took the test.

Answer 2

Temperature is directly proportional to the average kinetic energy of the molecules.

KE = 3/2 kT ...... where KE is the average kinetic energy of a molecule and k is Boltzmann's constant (1.381x10^-23 J/K).

KE = 3/2 RT ...... where KE is the average kinetic energy for a mole of molecules and R is the gas constant (8.314 J/molK).

Therefore, as KE decreases, T decreases and it gets cooler.

It gets cooler...as metal gains energy it becomes hotter and melts...

**The correct answer is C