. Ordinary hydrogen at room temperature is a mixture of
A: 75% o - Hydrogen + 25% p - Hydrogen
B: 25% o - Hydrogen + 75% p - Hydrogen
C: 50% o - Hydrogen + 50% p - Hydrogen
D: 1% o - Hydrogen + 99% p - Hydrogen
Ordinary hydrogen is an equilibrium mixture of 75% ortho hydrogen and 25% para hydrogen at room temperature.
The spins of two protons are in the same direction in ortho hydrogen,
The spins of two protons are in the opposite direction in para hydrogen.
Final Answer: Hence the correct answer is (A) 75% o - Hydrogen + 25% p - Hydrogen