Question

How are all atoms similar?

Answer 1

All things are made of atoms, and all atoms are made of the same three basic particles - protons, neutrons, and electrons. But, all atoms are not the same. The difference in the number of protons and neutrons in atoms account for many of the different properties of elements.

I hope this helps :)

Answer 2

Atoms are similar in the way that their nuclei contain only protons and neutrons.