Question

Which among the following statements about hydrogen is correct?

• A. Hydrogen has three isotopes of which protium is the most common
• B. Hydrogen never acts as cation ion
• C. Hydrogen ion H⁺, exsits freely in solution
• D. Dihydrogen does not act as reducing agent

Answer 1

The correct option is A

Hydrogen has three isotopes of which protium is the most common

Among the three isotopes of hydrogen, protium is the most common. In ionic salts, hydrogen exists as hydride $\left(H^{-}\right)$ ion and dihydrogen can act as reducing agent, hydrogen acts as both reducing and oxidising agent.