Question

what is the mass of 8.22×10²⁴ molecules of H2

Answer 1

1 mole ----------- 6.02 x 10²³ molecules
? mole ---------- 8.22 x 10²⁴ molecules

moles of H₂ = ( 8.22 x 10²⁴ ) x 1 / 6.02 x 10²³

 = 13.654 moles of H₂

Mass of H₂ :

Molar mass H₂ = 2.0 g/mol

moles of H₂ x molar mass H₂

( 13.654 ) x ( 2.0 ) = 27.308 g

hope this helps!