Electrons in an atom make up most of the of the atom, while the protons and neutrons make up nearly all of the of the atom.

Electrons in an atom make up most of the volume of the atom, while the protons and neutrons make up nearly all of the mass of the atom.

Explanation:

Most of the mass of an atom comes from its nucleus, in which protons and neutrons are found, both of these particles have approximately the same mass.

The atom is also composed of electrons rotating in orbitals around the nucleus, and they have little mass compared to a proton or neutron. But despite being much lighter than the particles in the nucleus, the electron cloud occupies most of the space or volume of the atom.

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