What is Mole ? — Free written notes for Chemistry - 9th on EduFlame Pakistan.
A mole is the SI unit for measuring the amount of a substance. One mole of any substance is defined as the amount that contains as many elementary particles (atoms, molecules, or ions) as there are atoms in exactly 12 grams of carbon-12.
Avogadro’s Number:
In simple terms, one mole of any substance contains 6.022 × 10²³ particles of that substance.
Molar Mass:
The molar mass of a substance is the mass of one mole of that substance in grams. It is numerically equal to the molecular or atomic mass of the substance.
Example:
The molar mass of water (H₂O) is 18 g/mol. This means 1 mole of water has a mass of 18 grams and contains 6.022 × 10²³ molecules of water.