STRUCTURE OF ATOM - Is it an atom?

ATOM = (protons + neutrons) + Electron

Atomic number = number of protons = number of neutrons in an atom 

Atomic mass number (mass) = mass of the neutron proton + 


Mass of proton = mass of neutron = 1.67 x10 -27 kg 
Electron mass = 9.11 X 10-31 kg 


The atomic mass unit (amu) as the unit of atomic weights, as is standard 


1 / 12 heavy atoms 12C = 1.66 x 10 -24 g = 1 amu 
The atomic weight is often expressed per mole (g / mol) 


One mole stating the number of particles that have mass in grams. 
The number of atoms in one mole is given by Avogadro's number, N = 6.023 x 1023