Ionization energy is the minimum energy required for an atom or molecule to lose an electron.

His first choice of school is the University of Tokyo.

The potential energy of this ball is proportional to its height.

He ate one apple.

I learned about the process of ionization in chemistry class.

I ionized hydrogen in a chemistry experiment.

Watching a movie alone is enjoyable.

We should use more renewable energy.

We are using LED bulbs for energy saving.

He expanded the company in one generation.