Ionic compounds are those compounds which are made up of ions. These ions can exist as positive or negative ions. Those ions which has tendency to lose electrons are said to be cations (positive ions) such as metals and those ions which has tendency to gain electrons are said to be anions (negative ions) such as non-metals.
The formula for ionic compounds are given as:
First, the symbols of the cation and anion should be identified. After that, charge on the cation and anion should be identified. Write the chemical formula with the help of drop and swap method.
Now,
The chemical symbols for Aluminium is [tex]Al[/tex] and for chlorine is [tex]Cl[/tex].
The charge on [tex]Al[/tex] is +3 and on [tex]Cl[/tex] is -1, neglect the positive and negative signs and by using drop and swap method i.e. the charge on the aluminium will go as a subscript of the chlorine and the charge on the chlorine will go as a subscript of the aluminium which is shown in the image.
Thus, the chemical formula between [tex]Al[/tex] and [tex]Cl[/tex] is [tex]AlCl_{3}[/tex].
