Answer:
1,5 moles of H₂
Explanation:
Avogadro's number is defined as a constant that relates the number of particles presents in 1 mole. This number is 6,022x10²³.
Thus, 9x10²³ molecules of hydrogen are:
9x10²³ molecules of hydrogen × (1 mole / 6,022x10²³molecules) =
1,5 moles of H₂
I hope it helps!