Over the years, the thermite reaction has been used for welding railroad rails, in incendiary bombs, and to ignite solid-fuel rocket motors. The reaction is the following.
3 NiO(s) + 2 Al(s) → 3 Ni(l) + Al2O3(s)

What is the maximum mass of aluminum oxide that could be produced?

(The question before this was "What masses of nickel(II) oxide and aluminum must be used to produce 15.3 g of nickel?" The answer being 19.47g NiO and 4.69g Al

Question

Over the years, the thermite reaction has been used for welding railroad rails, in incendiary bombs, and to ignite solid-fuel rocket motors. The reaction is the following.
3 NiO(s) + 2 Al(s) → 3 Ni(l) + Al2O3(s) 


What is the maximum mass of aluminum oxide that could be produced?

(The question before this was "What masses of nickel(II) oxide and aluminum must be used to produce 15.3 g of nickel?" The answer being 19.47g NiO and 4.69g Al

cuanchi · Answer

you have at least  two ways to solved
1) is considering the Law of conservation of mass, you have the mass of all your reactants and one of your products you can calculate the mass of the other product.
2) calculate the moles of Al in 4.69 g  and divided by two and multiply by the molecular mass of the Al2O3.
or 
3) calculate the moles of NiO in 19.47g  and divided by 3 and multiply by the molecular mass of the Al2O3.
4)calculate the moles of Ni in 15.3g  and divided by 3 and multiply by the molecular mass of the Al2O3.