The molar mass of atoms of an element is given by the relative atomic mass of the element multiplied by the molar mass constant, Mu = 0.99999999965(30)×10−3 kg⋅mol−1.
To calculate the molar mass of a molecule, we first obtain the atomic weights from the individual elements in a periodic table. We then count the number of atoms and multiply it by the individual atomic masses. Lastly, we add all the atomic masses together to get the molar mass.
Molar mass is generally defined as the mass of Avogadro number of atoms, molecules or compounds while molecular mass is defined as the sum of atomic masses of all the atoms which are present in the given molecule or compound.
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