Question #c0a6c

1 Answer
Feb 24, 2015



An atom is composed of a nucleus (protons and neutrons) and one or mores electrons.

See table:

The distance between nucleus and electron cloud is very large! See figure below:

Compare the mass of the electron with those of the proton and the neutron. The protons and the neutrons have a much higher mass and are concentrated in the nucleus.

Therefore, the mass of the atom is practically concentrated in its nucleus.