Question

How can we describe an atom

Answer 1

In simple terms an atom is a cloud of tiny electrons buzzing round a central much larger nucleus in a series of orbits called shells.

Answer 2

The smallest unit of an element, consisting of at least one proton and (for all elements except hydrogen) one or more neutrons in a dense central nucleus, surrounded by one or more shells of electrons. In electrically neutral atoms, the number of protons equals the number of electrons.