Final answer:
HCl and HNO3 are monoprotic acids, while H2SO4 is a diprotic acid, and H3PO4 is a triprotic acid. The correct answer to the question is d) H3PO4 (Phosphoric acid), which is a triprotic acid.
Step-by-step explanation:
The question asks us to identify which of the listed acids is a polyprotic acid. A polyprotic acid is one that contains multiple ionizable hydrogens and can donate more than one proton in a stepwise manner. Among the options provided:
- HCl (Hydrochloric acid) is a monoprotic acid as it can only donate one proton.
- H2SO4 (Sulfuric acid) is a diprotic acid as it can donate two protons.
- HNO3 (Nitric acid) is also a monoprotic acid, similar to HCl.
- H3PO4 (Phosphoric acid) is a triprotic acid as it is capable of donating three protons in successive steps.
Therefore, among the given options, both H2SO4 and H3PO4 are polyprotic acids. However, because H3PO4 can donate three protons, if we are to choose the one that is triprotic, the correct answer is d) H3PO4 (Phosphoric acid).