mass of Aluminum produced = = 2.647 kg
moles of Oxygen = 73.53 moles
Further explanation
Given
5.0 kg Al₂O₃
Required
moles of Oxygen
Solution
The aluminum oxide gets decompose into aluminum and oxygen gas.
Reaction :
2Al₂O₃(s)⇒ 4 Al(s) + 3O₂(g)
mol of Al₂O₃(MW=102 g/mol) :
= mass : MW
= 5000 g : 102 g/mol
= 49.02 moles
From the equation, mol ratio of Al₂O₃ : O₂ = 2 : 3, sol mol O₂ :
= 3/2 x mol Al₂O₃
= 3/2 x 49.02
= 73.53 moles
mol Al :
= 4/2 x mol Al₂O₃
= 2 x 49.02
= 98.04 moles
Mass Al :
= mol x Ar Al
= 98.04 x 27 g/mol
= 2647.08 g
= 2.647 kg