Theories of Acids and Bases and Salt Hydrolysis
The are three types of theories that involve acids and bases. They include Arrhenius, Brownsted-Lowry, and Lewis.
The Arrhenius Theory
It is the theory that states an acid release hydrogen ions when submitted into water. The definition of a base is the substance that is produces hydroxide ions when submitted into water.
The Brownsted-Lowry Theory
A Brownsted-Lowry acid is a species that donates a proton (H+)
A Brownsted-Lowry base is a species that accepts a proton.
Consider the following equation:
HNO3 (aq) + H2O(l) => NO3-(aq) + H30+(aq)
Under the Brownsted-Lowry definition of an acid, we can agree that HNO3 and H3O+ are both acids because they both donate protons. As for the remaining compounds, they are bases that both accept the protons from the acids. Since HNO3 gives a proton to NO3-, this can determine one of two conjugate pairs in the reaction. The other being between H3O+ and H2O. The conjugate base is defined as the species remaining after the acid loses its proton. For every base, it also has a conjugate acid, which is the species formed after the base has accepted a proton.
When a substance is described as being amphoteric, it implies that it can act as an acid or a base. An example is water (H2O). It is important to remember that strong acids pair up with weak conjugate bases and vice versa.
A Brownsted-Lowry base is a species that accepts a proton.
Consider the following equation:
HNO3 (aq) + H2O(l) => NO3-(aq) + H30+(aq)
Under the Brownsted-Lowry definition of an acid, we can agree that HNO3 and H3O+ are both acids because they both donate protons. As for the remaining compounds, they are bases that both accept the protons from the acids. Since HNO3 gives a proton to NO3-, this can determine one of two conjugate pairs in the reaction. The other being between H3O+ and H2O. The conjugate base is defined as the species remaining after the acid loses its proton. For every base, it also has a conjugate acid, which is the species formed after the base has accepted a proton.
When a substance is described as being amphoteric, it implies that it can act as an acid or a base. An example is water (H2O). It is important to remember that strong acids pair up with weak conjugate bases and vice versa.
Lewis Acids and Bases
According to the Lewis theory, an acid is any species that accepts lone pair electrons. On the other hand, a Lewis base is any species that donates lone pair of electrons.
