How many grams of Al2O3 can form from 36.3 g of Al

Question

36.3 g Al write the conversion and calculate the grams of Al2O3

Answer 1

This is a simple dimensional analysis problem, as long as you know 3 conversions:

1) The atomic mass of Al is 26.982, meaning that there are 26.982 grams Al / 1 mol Al

2) The atomic mass of Al2O3, found by adding up the atomic masses of each individual atom, is 101.96, meaning that there are 101.96 grams Al2O3 / 1 mol Al2O3

3) The reaction at hand is 6Al + 3O2 -> 2Al2O3. Therefore, there are 6 mol Al / 2 mol Al2O3, or 3 mol Al / 1 mol Al2O3.

With these conversions, you can do dimensional analysis:

36.3g Al * (1 mol Al / 26.982g Al) * (1 mol Al2O3 / 3 mol Al) * (101.9g Al2O3 / 1 mol Al2O3) = 45.7 g Al2O3 formed from 36.3 g of Al