Formation of Chemical Compound

Formation of Compound

                                      We get chemical formula of molecule by writing valence of 1^st atom in front of 2^nd atom and valence of 2^nd atom in front of 1^st atom.

Example: valence of carbon is 4 and oxygen is 2, write 4 in front of O and 2 in front of C in subscripts as shown below.

C₂O₄

as we see, both valences are multiple of two so divide it by two to get CO₂ formula.

Similarly,

           Na⁺ + CO₃^-2   ---> Na₂CO₃

          Al⁺3 + SO₄^-2  --->  Al₂(SO₄)₃

          Mg⁺² + N^-3    --->  Mg₃N₂