If 50g of aluminum is oxidized, what mass of alumina will be recovered?

1 Answer

Approx. 95g of alumina will be recovered.

Explanation:

We follow the stoichiometric equation........

2Al(s)+32O2(g)Al2O3(s)

And this 2 equiv of metal required 3/2 equivalents of dioxygen gas.

Moles of aluminum = 50g27.0gmol1=1.85mol.

And since aluminium is CLEARLY the so-called limiting reagent in this reaction (since we know precisely how much mass of Al reacted), at most we can get half an equiv of alumina....

And thus the mass of alumina is given by the product....

1.85mol×12×101.96gmol1=??g.

Look for videos on molar equivalence and stoichiometry on the web. Perhaps this one: