Historically the dining room is furnished with a rather large dining table and a number of dining chairs; the most common shape is generally rectangular with two armed end chairs and an even number of un-armed side chairs along the long sides.
Protons and neutrons do not have the same mass. Their masses are quite close, but they are noticeably different. For some purposes it is okay to equate the neutron and proton mass, but it's just an approximation.Also, neutrons decay into a proton, an electron and an antineutrino.rotons and neutrons do not have the same mass. Their masses are quite close, but they are noticeably different. For some purposes it is okay to equate the neutron and proton mass, but it's just an approximation.
Each proton and neutron has about the same amount of mass, measured in daltons, or atomic mass units (amus). Because the unit of measure is defined by one proton, 1 proton = 1 neutron = 1 dalton = 1 amu. Electrons do have some mass, but it is almost 2000 times less than the mass of a proton.hey come in different kinds, called elements, but each atom shares certain characteristics in common. All atoms have a dense central core called the atomic nucleus. Forming the nucleus are two kinds of particles: protons, which have a positive electrical charge, and neutrons, which have no charge.