Question

1. Name the phenomenon which causes the following changes :

( c ) Conversion of water into steam.

Answer 1

Boiling:

• Boiling is an extreme case of evaporation, it is the process in which a liquid substance changes into a gaseous state at atmospheric pressure, this occurs at a fixed temperature.
• The fixed temperature at which liquid substance changes into vapour or steam at atmospheric pressure is known as boiling point.
• For example the boiling point of water is 100°C.

Concluding statement: It is a process in which liquid changes into steam at a fixed temperature known as boiling.