# Molar Mass

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 ${\displaystyle C_{6}}$ (12) atoms in exactly 12.00000g of ${\displaystyle C_{6}}$ (12) i.e. in 12.00000g of ${\displaystyle C_{6}}$ (12) there are ${\displaystyle 6.022137*10^{2}3}$ atoms of ${\displaystyle C_{6}}$ (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 ${\displaystyle C_{6}}$ (12): 12 amu, thus, 1 mole of ${\displaystyle C_{6}}$ (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.

${\displaystyle NO_{2}}$ 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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