What is the total number of moles of hydrogen gas contained in 9.03 * 1023 molecules?

1.5 mol.

Explanation:

It is known that every 1.0 mole of compound or element contains Avogadro's number (6.022 x 10²³) of molecules or atoms.

Using cross multiplication:

1.0 mole of H₂ contains → 6.022 x 10²³ molecules.

? mole of H₂ contains → 9.03 x 10²³ molecules.

∴ The no. of moles of H₂ contains (9.03 x 10²³ molecules) = (1.0 mol) (9.03 x 10²³ atoms) / (6.022 x 10²³ atoms) = 1.5 mol.