Question

How many grams of oxygen is needed to completely react with 9.30 moles of Al

Answer 1

Answer: 223.2 grams

Explanation:

According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.

$4Al+3O_2\rightarrow 2Al_2O_3$

According to the given balanced equation:

4 moles of Aluminium reacts with 3 moles of oxygen .

Thus 9.30 moles of Aluminium reacts with=$\frac{3}{4}\times 9.30=6.975moles$ of oxygen.

Mass of Oxygen gas = Moles × Molar mass = 6.975mole × 32 g/mol = 223.2 g