phase change
phase transition
state change
physical change

A gas can go through two different state changes.

In a couple of years, the political scene in the state changes.

Once commerce and communication take place beyond national control, the status of the state changes.

Two other approaches exist to lowering the power cost of state changes.

To take the state change into account as well, we define what is called an instrument.

Tip the pressure one way, and the state changes.

I suppose one state changes into another to prevent the edge being taken off the suffering.

But you leave the mill and your mental state changes.

The detectable condition will typically be seen as a state change.

The head of state changes, but the citizens remain.