Question

what are elementary entities

Answer 1

elementary entities are any of several entities, such as electrons, neutrons, or protons, that are less complex than atoms and are regarded as the constituents of all matter.

Answer 2

The number of constitutive entities in simple of a substance technically called (its chemical) amount.Therefore,the mole is a unit for that physical quantity.One can determine the chemical amount of a known substance,one mole,by dividing the sample's mass by the substance's molar mass.