An atom is made up of protons, neutrons, and electrons.
When an atom is charged, it becomes an ion.
The breaking down of atoms is what provides nuclear energy.
A molecule may be defined as the smallest part of a substance which can exist alone; an atom as the smallest part of a substance which can exist in combination.
I couldn't find an atom of hatred in the sweet, innocent girl.
Some elements only exist in nature in pairs of atoms, including hydrogen, nitrogen, and iodine.
There's not an atom of dirt in her house because she never stops cleaning.
What atom is most prevalent in Earth's atmosphere?