The chemical equation below shows the formation of aluminum oxide (al2o3) from aluminum (al) and oxygen (o2).

4al + 3o2 > 2al2o3

the molar mass of o2 is 32.0 g/mol. what mass, in grams, of o2 must react to form 3.80 mol of al2o3?

60.8
81.1
122
182

182 grams of oxygen gas must react to form 3.80 mol of aluminum oxide.

Explanation:

Moles of aluminum oxide = 3.80 mole

According to reaction, 2 moles of aluminum oxide is obtained from 3 moles of oxygen gas.

Then 3.80 moles of aluminum oxide will be obtained from:

of oxygen gas.

Mass of 3.80 moles of oxygen = 5.7 mol × 32 g/mol = 182.4 g ≈ 182 g

182 grams of oxygen gas must react to form 3.80 mol of aluminum oxide.