Question

Which of the following statements about Hydrogen is incorrect?

• A. Hydrogen has three isotopes, of which, tritium is the most common
• B. Hydrogen never acts as cation in ionic salts.
• C. Hydronium ion, H₃O⁺ exists freely in solution.
• D. Dihydrogen does not act as a reducing agent

Answer 1

The correct option is A

Hydrogen has three isotopes, of which, tritium is the most common

Explanation of correct option

Isotopes of hydrogen: There are three known isotopes, of hydrogen, each possessing an atomic number 1 and atomic masses 1,2 and 3 respectively,
these are named protium, deuterium, and tritium.

• Protium: This isotope constitutes 99.984 per cent of the total hydrogen available in nature.
• Deuterium: It constitutes only 0.016 per cent of the total hydrogen occurring in nature.
• Tritium: It constitutes 1 x 10^-15 per cent of the total natural hydrogen.

The most common available isotope of hydrogen is protium, not tritium.

Explanation of Incorrect option

Properties of hydrogen:

• Hydrogen is a colourless, odourless, and tasteless gas.
• Hydrogen is only slightly soluble in water, about 2 volumes in 100 volumes of water at 0°C.
• Hydrogen is the lightest of all elements.
• Hydrogen is diatomic in nature.
• Hydrogen has low melting and boiling points
• Hydrogen never acts as a cation in ionic salts.
• Hydronium ion, H₃O⁺ exists freely in solution.
• Dihydrogen does not act as a reducing agent

Hence, Option (A) is the correct option.