Yes, significantly so. One proton is approximately one atomic mass unit.
Mass of an atom = Mass of proton + Mass of neutron
Proton + Nuetron = Atomic Mass
1.007316 (amu)
proton
proton
in the nucleus of an atom -proton and neutrons , electrons in the orbit has the negligible mass.
The positively charged particle in an atom is the proton. The negatively charged particle is the electron. The electrically neutral particle is the neutron.
The three main sub-atomic particles of an atom are proton, neutron and electron. The mass of a proton is about 1800 times the mass of an electron and the masses of proton and neutron are almost similar. Hence, mass of only proton and neutron is counted towards the mass of an atom.
mass number
No.
Proton and neutron have similar mass, but not identical.
atomic mass means he weight of atom so electron is lighter than proton and neutron thats why it not count in mass of atom