What particles contribute to the mass of an atom?

Protons and Neutrons

Explanation:

Since the nucleus of an atom contribute to the mass of atom and protons and neutrons are present inside so proton and neutrons contribute to the mass of an atom. Electron is not so heavy particle so it won't contribute to the mass of an atom.

convalent bond :

is a chemical bond formed by the sharing of electron between 2 atoms.

it is the direct chemical bond between 2 atoms.

in bond formation atoms are involved here.

electrovalent bond:

is a chemical bond defined as electroststic attraction between 2 atoms.

it is the electrostatic attraction between 2 atoms.

in bond formation, ions are involved here.

hope it

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