Types of Chemical Compounds and Their Formulas
The combination of symbols, known as chemical formula, is used to represent a compound.
The chemical formula of compound indicates;
1) the elements present
2) the relative numbers of atoms of each element in the compound.
A formula unit is the smallest collection of atoms on which the formula of a compound can be based.
A molecule of a compound is a group of bonded atoms that actually exist and can be identified as a distinct entity.
Atoms of almost all elements can gain or lose electrons to form charged species called ions. Compounds composed of ions are known as ionic compounds. i.e., combinations of metals and nonmetals usually result in an ionic compound.An ionic compound is a compound made up of positive and negative ions joined together by electrostatic forces of attraction.Metals tend to lose electrons to form positively charged ions called cations. Non-metals tend to gain electrons to form negatively charged ions called anions.