Question

What happens to the internal energy of an ideal gas when it is heated from 0C to 4C?

a. increases
b. decreases
c. change in number of atoms
d. increase in volume of substance

Answer 1

when temp increase,that mean average KE increase,if state change from solid to liquid or liquid to solid ,potential energy increase

For IDEAL GAS,it wont change to any state under HIGH TEMP LOW PRESSURE,so average KE increase but potential energy remains unchange

as far as we know,

INTERNAL ENERGY = AVERAGE KE + AVERAGE PE

SO,
THE ANS:A

for c,it is incorrect,because we didn't inject any gas ,so no of mole doesnt change and therefore no change in no of atoms

for d,change of internal energy, not equal to increase of volume of substance,please remember that internal energy is independent of the volume of the substance