I ionized hydrogen in a chemistry experiment.

I learned about the process of ionization in chemistry class.

This process takes time.

I like to study new languages.

I will teach mathematics to new students tomorrow.

I attended a math class today.

I use processed cheese for sandwiches.

He is majoring in chemistry at university.

He is an expert in chemistry.

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