How many moles of Al2O3 can be formed from 10.0 g of Al?

 0.185moles of Al₂O₃

Mass of Al = 10g

Mass of O₂ = 19g

Equation of the reaction: 4Al + 3O₂ → 2Al₂O₃

This is the balanced reaction equation.

Solution

From the given parameters, the reactant that would determine the extent of the reaction is Aluminium. It is called the limiting reagent. Oxygen is in excess and it is in an unlimited supply.

Working from the known mass to the unknown, we simply solve for the number of moles of Al using the mass given.

Then from the equation, we can relate the number of moles of Al to that of Al₂O₃ produced:

Number of moles of Al =  

                                       =    

                                       = 0.37mol

From the equation:

        4 moles of Al produced 2 moles of Al₂O₃

   0.37 mole will yield:   = 0.185moles of Al₂O₃

a is the correct answer