Multiply the subscript following each element symbol (the number of atoms) by the atomic mass of that element.Look up each element’s relative atomic mass in the formula.To determine the mass, use the molecular formula.The gram molecular mass (g/mol) can be expressed in grams or grams per mole (g/mol). The main distinction is that gram molecular mass defines the mass unit. The molar mass and gram molecular mass are the same things. The mass in grams of one mole of a molecular material is known as the gram molecular mass. Mass of the element (in g) = Number of gram atoms / Atomic mass of the element (in g) Gram Molecular Mass If we wish to write a substance’s gram atomic mass, we first write its atomic mass, then subtract the atomic mass unit u and add grams to the numerical value of the atomic mass.
![molar mass of h2 molar mass of h2](https://i.ytimg.com/vi/z0DyNd9nt0g/maxresdefault.jpg)
The gram atomic mass of a material is the amount of that substance in grams that is numerically equivalent to its atomic mass. This implies that the quantity of the element of the given substance when weighs equal to its gram atomic mass is called one gram atom. So one mole of sodium atoms weighs 22.99 g. Similarly, sodium (Na) has an atomic weight of 22.99 u and a gram atomic mass of 22.99 grams. For example, the gram atomic mass of helium is 4 g. Thus, when the mass of an element is expressed in grams then it is known as gram atomic mass. It is calculated by taking an element’s atomic weight from the periodic table and converting it to grams. The molar mass of an element is the mass of one mole in grams. The mass of one mole of an element is defined as its gram atomic mass. Gram atomic mass is the periodic table element’s atomic weight in grams. The term ‘Avogadro’s Constant’ is termed after the great pioneer Amedeo Avogadro. The value of 1 mole is known as Avogadro’s Constant. As measured by mass spectrometer the mass of one atom of C-12 atom is found to be 1.992648 × 10 -23 g.
![molar mass of h2 molar mass of h2](https://i.ytimg.com/vi/QPp_1FOta6c/maxresdefault.jpg)
The SI unit of molar mass is kg/mol however g/mol is the usually used unit.
![molar mass of h2 molar mass of h2](https://hi-static.z-dn.net/files/df4/0a5f0877756354300436c977694b3780.jpg)
the molecular mass of NH 3 = 14 + 1 × 3 = 17 a.m.u.
![molar mass of h2 molar mass of h2](https://prod-qna-question-images.s3.amazonaws.com/qna-images/question/4656f3e1-15fe-4057-8a63-ae7e210bd917/7b291bfe-6ce3-4285-a6b9-07206ccd8312/2tl4xtl_processed.png)