Monoprotic acid are -
Monapratic acids (HA) can donate 1 proton (H+) per molecule. Examples are hydrochloric acid (HCl), nitric acid (HNO3), formic acid, acetic acid, lactic acid and benzoic acid.
Polyprotic acids can donate more than one protons (H+) per molecules. These can be divided into :-

(i) Diprotic acid (H2A) :- These can donate upto 2 protons (RE) per molecule. Examples are carbonic acid, sulphuric acid, succinic acid and glutaric acid.
(iii) Triprotic acid (H3A) :- These can donate upto 3 protons (H+) per molecule. Examples are phosphoric acid and citric acid.
Formic acid
Acetic acid
Nitric acid
All of these