Question

calculate the equivalents mass of Al2O3 in the given reaction

4 Al + 3 O2 -----------> 2 Al2O3

Answer 1

4Al + 3O2 = 2Al2O3

Molar mass of Al = 27 g

Molar mass of Oxygen molecule = 32 g

Hence the Al and oxygen reacted in 1:1 molar ratio

Al is the limiting reactant as there is not sufficient of it to react with excess oxygen, as from the equation 1 mole of Al forms half mole of aluminium oxide, the molar mass of aluminium oxide is 27*2 + 16*3 = 102

Hence mass of Aluminium oxide formed = 102/2=51 g