# 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 (12) atoms in exactly 12.00000g of (12) i.e. in 12.00000g of (12) there are atoms of (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 (12): 12 amu, thus, 1 mole of (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.

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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