(1) Spontaneous process : It is defined as a process that takes place on its own or without the intervention of the external agency or influence. For example, expansion of a gas or flow of a gas from higher pressure to low pressure or a flow of heat from higher temperature to lower temperature.
(2) Characteristics :
- It occurs on its own and doesn’t require external agency.
- It proceeds in one direction and can’t be completely reversed by external stimulant.
- These processes may be fast or slow.
- These processes proceed until an equilibrium is reached.
