Atomic Mass :
Atomic mass of an element is the number of times the atom of the element is heavier than 1/12th of C-12 atom.
Atomic Number :
Atomic number of an element is the number of protons or electrons present in neutral atom of element.
Molecular Mass :
It is equal to the sum of atomic masses of all the atoms contained in the molecule.
Molar mass :
= Atomic mass or molecular mass in grams
Mole is a unit of numbers just like dozen ...
As 1 dozen = 12,
1 mole = 6.023 × 10 ²³ (This no. is known as Avogadro's no. or Avogadro's constant)
1 mole of anything ( like bananas, pencils, cars, atoms, etc.) = 6.023 × 10 ²³