the mass of an atom of a chemical element expressed in atomic mass units. It is approximately equivalent to the number of protons and neutrons in the atom (the mass number) or to the average number allowing for the relative abundances of different isotopes.
The particle you are describing is an atom of iron. The number of protons in an atom determines its atomic number, which is 26 for iron. The sum of protons and neutrons gives the atomic mass number, which is 56 for this iron atom.
The Electron.
The atom loses mass when a beta particle is released because a neutron decays into a proton, electron, and antineutrino. The mass of the neutron is greater than the combined mass of the resulting proton, electron, and antineutrino.
It would be neutrons.
A neutral particle in an atom is typically found in the nucleus, such as a neutron. Neutrons have no charge and contribute to the atomic mass of the atom.
Protons, neutrons and electrons
Neutrons are the particles that contribute to the mass of an atom, along with protons. Neutrons have a similar mass to protons, but they do not have a charge. The number of protons and neutrons in an atom's nucleus determines its atomic mass.
Protons, neutrons and electrons
nuclei
Which particle? The electron.
The particle you are describing is an atom of iron. The number of protons in an atom determines its atomic number, which is 26 for iron. The sum of protons and neutrons gives the atomic mass number, which is 56 for this iron atom.
The proton.
The number of protons, which is the atomic number of an element, determines the identity of an element.
neutron
The Electron.
A positively charged particle in an atom is the proton. Protons are found in the nucleus of the atom along with neutrons, and they carry a positive charge equal in magnitude to the negative charge of the electron. The number of protons in the nucleus determines the atomic number of an element.
Mass of electron is not included for the calculation of mass of an atom.