how to find how many moles are in particles?
['1 + 1 = 2 moles of He atoms.', '= Avogadro number + Avogadro number = 2 × Avogadro number of He atoms.', '= NA + NA = 2 × NA He atoms.', '= (6.022 × 1023) + (6.022 × 1023) = 2 × (6.022 × 1023) He atoms.']