Molar Mass

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In chemistry, Molar mass is a physical property characteristic of a given substance, namely its mass per amount of substance.

1.The Mole

One mole (mol) is the amount of a substance that contains as many elementary units as there are $C_{6}$ (12) atoms in exactly 12.00000g of $C_{6}$ (12) i.e. in 12.00000g of $C_{6}$ (12) there are $6.022137*10^{2}3$ atoms of $C_{6}$ (12).

2.Molar Mass

- Molar Mass of an Element is the mass in grams that is numerically equivalent to the atomic mass of that element (units g/mol).

Atomic mass of $C_{6}$ (12): 12 amu, thus, 1 mole of $C_{6}$ (12) atoms weighs 12g/mol.

- Molar Mass of a Compound is the mass in grams that is numerically equivalent to the formula mass of that compound.

$NO_{2}$ formula mass: 46.01 amu, molar mass: 46,01 g/mol.

                     THE MOLAR MASS OF ANY SUBSTANCE IS THE MASS IN GRAMS OF ONE MOLE OF THAT SUBSTANCE (UNITS g/mol)

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