Please help, what would the theoretical yield of this be? I don’t understand how to do this.

The theoretical yield : = 28.34 g Al₂O₃

Given

15 g of Aluminum react

Required

The theoretical yield

Solution

Reaction

4Al(s) + 3O₂ (g)⇒ 2Al₂O₃(s)

mol of Aluminum :

mol = mass : Ar Al

mol = 15 g : 26.98 g/mol

mol = 0.556

From the equation, mol ratio of Al : Al₂O₃ = 4 : 2, so mol Al₂O₃ :

= 2/4 x mol Al

= 2/4 x 0.556

= 0.278

Mass Al₂O₃ :

= mol x MW Al₂O₃

= 0.278 x 101.96

= 28.34 g