Question

At 0K, hydrogen contains mainly ______ hydrogen which is more stable.

• A. ortho
• B. para
• C. ortho and para both
• D. ortho and para by the ratio 1:3

Answer 1

The correct option is B para

The hydrogen molecules in which the spins of both the nuclei are in the same direction are called ortho-hydrogen molecules whereas if the spins of both the nuclei are in the opposite direction, the hydrogen molecule is para-hydrogen.

At 0K, hydrogen contains mainly para-hydrogen which is more stable.

Answer: (B) para