Question

What mass of AI2O3 forms from 16 g O2 and excess AI?

Answer 1

2Al+1.5O2→Al2O3

Thus, 2 mol of Al combine with 1.5 mol of oxygen to form 1 mol of Al2O3.

2 mol of Al corresponds to 2×27=54 g.

Thus, the weight of Al used in the reaction is 54 g.