Answer:275.4 g Al2O3
Explanation: The mass of Al2O3 formed is 2.7 mol * 102 g/mol = 275.4 g. This is because the molar mass of Al2O3 is 102 g/mol. This means that when 1 mol of Al2O3 is formed, it has a mass of 102 g. Therefore, when 2.7 mol of Al2O3 is formed, it has a mass of 2.7 mol * 102 g/mol = 275.4 g.