An Acid-Base Neutralization is a reaction where an acid and base react to form a salt. When considering the Arrhenius definition of acids and bases, a neutralization reaction should also produce water in addition to the salt.
Consider the following reaction:
HA + BOH --> AB + H2O
HA is the acid
BOH is the base
AB is the salt
H2O is the water produced by the neutralization reaction
The net ionic equation for the above reaction can be written as follows:
H+ + OH- --> H2O
Although many people think that neutralizations result in a pH of 7 (which is indicated by the color green using a universal indicator), this is not the case as it depends very much on the respective strength of the acid and the base. Consider the neutralization pH of the following pairs:
Strong acid – Strong base: pH = 7
Strong acid – Weak base: pH < 7
Weak acid – Strong base: pH > 7
Weak acid – Weak base: pH = 7
Thus, understanding neutralization reactions is an extremely important component for grasping the concept of acid-base reactions.