The mass of one mole of H₂ (hydrogen gas) is approximately 2 grams. This is because the molar mass of hydrogen (H) is about 1 gram per mole. Since H₂ consists of two hydrogen atoms, the total molar mass is 2 grams per mole.
To break it down further:
- The atomic mass of hydrogen (H) is approximately 1 atomic mass unit (amu).
- One mole of any substance contains Avogadro’s number of particles, which is approximately 6.022 × 10²³ particles.
- Therefore, one mole of H₂ molecules (each consisting of two hydrogen atoms) has a mass of 2 grams.
This calculation is fundamental in chemistry for converting between the mass of a substance and the number of moles, which is essential for stoichiometric calculations in chemical reactions.