(a)[2]
State the meaning of the internal energy of a system.
(b(i))[3]
Explain, with reference to work done and heating, whether the internal energy of the gas in a toy balloon, when the balloon bursts suddenly, increases, decreases or stays the same.
(b(ii))[3]
Explain, with reference to work done and heating, whether the internal energy of ice as it melts at constant temperature and at atmospheric pressure to produce water that is more dense than the ice increases, decreases or stays the same.