What are the atomic masses of protons, neutrons, and electrons?
The atomic mass of a proton is approximately 1 unified atomic mass unit (u), which is equivalent to 1.00727 atomic mass units.
The atomic mass of a neutron is also approximately 1 unified atomic mass unit (u), which is slightly higher at 1.00867 atomic mass units.
The atomic mass of an electron is significantly smaller, and it is considered to be negligible compared to the mass of a proton or neutron. The mass of an electron is approximately 0.00054858 atomic mass units.