What we have seen for water goes for any substance. Both the
liquid and gas states can exist at the boiling point. What
happens depends on whether energy is
gained or lost.
For a sample of a substance at its boiling point:
 |
if energy is being
gained it changes from the liquid
to the gas state; |
|
if energy is being
lost it changes from the gas
to the liquid state; |
|
if energy is neither
gained nor lost, it will stay as it is: no boiling or
condensing. |
|
The
table shows how much energy is involved for some substances
and their melting points:
| Substance |
Energy involved
in change between
liquid and gas
states for 1g |
|
|
| Lead |
867 joules |
| Water |
2261 joules |
| Salt |
2223 joules |
| Oxygen |
213 joules |
| Propanone |
522 joules |
|
|
|
