Question

Explain the concept of acid and base?

Answer 1

Acid: an acid is a chemical substance that is sour in taste, they turn blue litmus to red, and they react with bases to form salts.
Base: A base is a chemical substance that is bitter in taste, they turn red litmus to blue, and they react with acids to form salts.
Arrhenius Theory of acids and bases:
Acids are substances that produce hydrogen ions($H^{+}$) in solution. For example, HCl produces hydrogen ions in solution.
Bases are substances that produce hydroxide ions($O{H}^{-}$) in solution. For example, NaOH produces hydroxide ions in the solution.

Bronsted–Lowry Theory of acids and bases:
According to Bronsted-Lowry theory,
acid is a substance that donates an $H^{+}$ ion or a proton and forms its conjugate base and
the base is a substance that accepts an $H^{+}$ ion or a proton and forms its conjugate acid.

For example, in a reaction between acetic acid and water, acetic acid donates a proton and acts like acid and a water molecule (base) takes a proton

Lewis Theory of acids and bases:
According to lewis's theory, Lewis acids accept an electron pair. For example; $B{F}_3,ZnC{l}_2$

According to lewis's theory, Lewis bases donate an electron pair. For example; $N{H}_3,P{H}_3$