Atoms and Molecules long 5

Question 1

What are the rules of a chemical formula ?

Answer 1

They are-

• The charges on the ion must balance.
• When a compound consists of a metal and a non-
  metal, the name or symbol of the metal is written
  first.
• In compounds formed with polyatomic ions the it is indicated by enclosing the formula of ion in a bracket and writing the number of ions outside the bracket.