what is the differenc between molecular …

Molecular mass gives the mass of a single molecule (sum of the atomic masses in the molecule), whereas molar mass gives the average mass of the molecule (mass of Avogadro number of molecules).

– Therefore, the molecular mass of a molecule containing heavier isotopes can be few units higher than the molar mass.

– Otherwise, the value of the molar mass and molecular mass is quiet the same for a similar molecule; only the units are different. The unit of the molecular mass is amu, and the unit of the molar mass is gmol-1.

– It is accurate to use the molecular mass in calculations of higher amounts of molecules than using the molar mass.

– Molar mass is a measurement, which can be given to atoms, molecules or compounds. But molecular mass is only determined in the molecules. If it is the mass of an atom, a different terminology called atomic mass is used.