Chemical Reactions and Equations
Chemical reactions are the processes in which new substances with new properties are formed. The conversion of reactants into products in a chemical reaction is accompanied by some characteristic features.
The representation of a chemical reaction with the help of chemical symbols and formulae of substances involved in it is called chemical equation.
Skeletal chemical equation has an unequal number of atoms of reactants and products.
A chemical reaction is balanced when the number of atoms of each element on both sides of arrow is equal.
There are three methods to balance a chemical equation hit and trial method, oxidation number method and ion electron method. There is one common basic principle in the above three methods, i.e. Law of conservation of mass.
Combination reaction, decomposition reaction, displacement reaction, double displacement reaction, oxidation-reduction reaction are some important types of chemical reactions.
In a combination reaction two or more substances combine to form a single substance.
Decomposition reaction is opposite to combination reaction. In decomposition reaction a single substance is broken into two or more simpler substances.
When an element displaces another element from its compound, a displacement reaction occurs.
Two different atoms or groups of atoms are exchanged in double displacement reactions.
A reaction in which reduction and oxidation takes place simultaneously is known as redox reaction or oxidation-reduction reaction.
Have you observed the effects of oxidation reactions in everyday life?
Corrosion of metals and rancidity are the common examples of oxidation reaction in daily life.
Corrosion is a process in which metals are eaten up gradually by the action of air, moisture or chemical on their surface.
Rancidity is the deterioration of fatty and oily food by the oxidation leading to unpleasant smell and taste.