The mole concept
Amount in moles (n) is a important quantity in chemical calculations as the same amount in moles of two substances contain the same number of formula units of those substances.
The number of particles in one mole has been determined experimentally to be 6.022 × 1023. The Avogadro constant () is equal to 6.022 × 1023 mol–1.
The coefficients in the balanced equation for a reaction give the ratio of
Thus the coefficients also give the ratio of
In 1 mol NaCl the number of NaCl units equals the number of C6H12O6 units in 1 mol C6H12O6.
The number of particles in one mole has been determined experimentally to be 6.022 × 1023. The Avogadro constant () is equal to 6.022 × 1023 mol–1.
The coefficients in the balanced equation for a reaction give the ratio of
- the number of formula units of reactants required for complete reaction to
- the number of formula units of products formed.
2H2 + O2 
2H2O 2 molecules of H2 plus 1 molecule of O2 gives 2 molecules of H2O 2 moles of H2 plus 1 mole of O2 gives 2 moles of H2O
Thus the coefficients also give the ratio of
- amounts in moles of reactants required for complete reaction.
- amounts in moles of products formed to the amount in moles of reactants used.