Question

If transfer of $H_2$ gas occurs from north pole to desert area, which form of hydrogen is stable?

• A. Ortho
• B. Para
• C. Both
• D. None

Answer 1

The correct option is A Ortho

Molecular hydrogen occurs in two isomeric forms, one with its two proton spins aligned parallel (orthohydrogen), the other with its two proton spins aligned antiparallel (parahydrogen).

At room temperature and thermal equilibrium, hydrogen consists of approximately $75\%$ orthohydrogen and $25\%$ parahydrogen. The para form dominates at low temperatures $($approx. $99.8\%$ at $20$ K$)$.

At the north pole, the temperature is very low and in the desert, the temperature is high so, at the desert level, the ortho form is stable.

Option A is correct.