It' s also constant: you don' t have to do anything to make an hour go by.

Because so much of what we do in chemistry does take place with constant temperature and pressure.

It feels like anxiety, like a constant unsettling sense that something is wrong.

Do this throughout your day, and you will be in a constant state of relaxation and enjoyment.

You know how pressure changes with temperature at constant volume if you know the equation of state.