Mole Concept

Mole Concept
 

Solved Examples
Example: Calculate the number of moles of H, S and O in 5 moles of H₂SO₄.

Solution: 1 molecule of H₂SO₄ contains 2 atoms of H, 1 atom of S and 4 atoms of oxygen.
    1 mole of H₂SO₄ contains 2 moles of H.
    \(\therefore\)5 moles of H₂SO₄ contains 10 mole of H.
    1 mole of H₂SO₄ contains 1 mole of S.
    or  5 moles of H₂SO₄ contains 5 moles of S.
    Similarly 
    1 mole of H₂SO₄ contains 4 moles of O.
    or  5 moles of H₂SO₄ contains 20 moles of O.

Example:    Calculate the mass of one mole of electrons?
Solution :  Mass of one electron = 9.1095 × 10^–31kg
Mass of one mole electrons = 9.1095 × 10^–31 × 6.022 × 10²³ = 5.5 × 10^–7 Kg
                                                                                         = 0.55 mg
Example:    Calculate the charge of one electron?
Solution : Charge of 6.022 × 10²³ electrons = 96,500 coul.
Charge of one electron = \( \frac{{96500}} {{6.022}} \) × 10^–23
                    = 1.602 × 10^–19  coul.