What is molar mass and molecular …

Molecular Mass:  Molecular mass of a compound is the mass of a one molecule. This is measured by atomic mass units (amu). 1 atomic mass unit is the one twelfth of the mass of a C-12 isotope. When a mass of a molecule is divided by the mass of one twelfth of the mass of a C-12 isotope, its relative mass is obtained. Molecular mass differs due to the isotopes in which molecule is made up of. When calculating the molecular mass, the relevant isotopic mass should be considered.
Molar Mass: This is also known as molecular weight. It is the mass of a substance for a given amount. The SI unit for the molar mass is g mol-1. This gives the amount of the atoms/molecules/compounds present in one mole of the substance. In other words, it is the mass of Avogadro number of atoms/molecules or compounds. It is important to measure the weight of atoms and molecules in the practical scenario. But it is difficult to weigh them as individual particles, since their masses are really small according to the normal weighing parameters (such as grams or kilograms). Therefore, to fulfill this gap and to measure the particles in a macroscopic level molar mass concept is useful. The definition of molar mass is directly related to the carbon-12 isotope. The mass of one mole of carbon-12 atoms is exactly 12 grams, which is its molar mass, it is exactly 12 grams per mole. Molar mass of molecules containing the same atom like O₂ or N₂ is calculated by multiplying the number of atoms by the molar mass of the atoms. Molar mass of the compounds like NaCl or CuSO₄ is calculated by adding the atomic masses of each atom.