Mention any two important rules for writing a chemical formula

cbse
atomsandmolecules

#1

(i) Give one word for the following:
(a) Positively charged ion
(b) A group of atoms carrying a charge
(ii) Mention any two important rules for writing a chemical formula.


#2

(i) (a) Cation
(b) Polyatomic ion
(ii) Two rules for writing a chemical formula are:
(a)When a compound consists of a metal and a non-metal, the symbol of the metal is written first and on the left whereas of non-metal on its right.
(b)The valencies or charges on the ions must be balanced in the chemical formula.