The molar mass, also known as molecular weight, is the sum of the total mass in grams of all the atoms that make up a mole of a particular molecule. The molar mass of a substance is the molecular weight, but it is expressed in grams, not in amu. There are two types of molar pregnancy, complete molar pregnancy and partial molar pregnancy. The molar mass of sodium chloride is known; it is 58.44 g mol −1. A molar pregnancy — also known as hydatidiform mole — is a rare complication of pregnancy characterized by the abnormal growth of trophoblasts, the cells that normally develop into the placenta. When we know the number of moles needed, the concept of molar mass can be used to calculate how many grams of substance are required. The molar mass of a compound is calculated by the sum of the standard atomic weights of the atoms forming it multiplied by the constant of the molar mass (6,002×1023). Molar mass. It can also be defined as the weight of a mole of a substance (in gm or kg), in which there are 6.022 × 1023 atoms of the substance. For example, to calculate the grams mol of hydrochloric acid it is necessary to know the values of the elements that make up this compound in the periodic table. The name and formula are both provided for use in calculating molar mass. The unit used to measure is grams per mole. The representative particles can be atoms, molecules, or formula units of ionic compounds. The molar mass of a substance is the mass of 1 mole of that substance, in multiples of the gram. The molar mass links the mass of a substance to its moles. Thus, by knowing the molar mass, we can determine the number of moles contained in a given mass of a sample. Learn with flashcards, games, and more — for free. Exact Mass: 126.90447 g/mol: Computed by PubChem 2.1 (PubChem release 2019.06.18) Monoisotopic Mass: 126.90447 g/mol: Computed by PubChem 2.1 (PubChem release 2019.06.18) Topological Polar Surface Area: 0 Ų: Computed by Cactvs 3.4.6.11 (PubChem release 2019.06.18) Heavy Atom Count: 1: Computed by PubChem: Formal Charge-1: … The molar mass of the chemical substance is equal to the sum of the atomic mass of the individual atoms. This relationship is frequently used in the laboratory. The molar mass of any substance is the mass in grams of one mole of representative particles of that substance. We can use a measurement of any one of the following properties to determine the molar mass (molecular weight) of an unknown that is the solute in a solution: All you need to do is calculate the molecular weight and stick the unit "g/mol" (grams per mole) after the number (instead of amu) and that is the molar mass for the substance in question. Let me make it more clear with an example of sodium chloride. Determining Molar Mass. For most practical purposes, the magnitude of molar mass is numerically the same as that of the mean mass of one molecule, expressed in daltons. The amount of substance is the number of moles in the sample. Molar mass is a smallest unit of a compound with one twelfth of the mass of one carbon – 12 atoms. Molar mass is the physical property of a substance and is denoted by 'M'. Given. Atomic mass of H = 1u; Atomic mass of N = 14 u; Atomic mass of O = 16u; The molar mass of HNO3 is (1 × 1) +(1 × 14) + (16×3) = 63 u.