Answer:
Al2O3(s) +3CO(g) → 2Al(s) + 3CO2(g)
Step-by-step explanation:
Step 1: data given
Aluminium oxide = Al2O3
carbon monoxide = CO
aluminium metal = Al
carbon dioxide = CO2
Step 2: The unbalanced equation
Al2O3(s) + CO(g) → Al(s) + CO2(g)
Step 3: Balancing the equation
Al2O3(s) + CO(g) → Al(s) + CO2(g)
On the left side we have 2x Al (in Al2O3), on the right side we have 1x Al. To balance the amount of Al, we have to multiply Al on the right side by 2
Al2O3(s) + CO(g) → 2Al(s) + CO2(g)
On the left side we have 4x O, on the right side we have 2x O. To balance the amount of O on both sides, we have to multiply CO on the left side by 3 and CO2 on the right side by 3. Now the equation is balanced.
Al2O3(s) +3CO(g) → 2Al(s) + 3CO2(g)