Aluminum oxide empirical formula

Aluminum reacts with oxygen to yield aluminum oxide. If 5.0 g of A1 reacts with 4.45 g of 02, what is the empirical formula of aluminum oxide ... 

The manufacture of molded articles is usually carried out with mixtures of aluminum oxides with different particle size distributions. This is particularly important when pore-free end-products are required, because this enables a higher volume concentration of aluminum oxide to be obtained than the 74% of ideally cubic close packed spheres by filling the gaps with smaller particles. The particle size distributions used in practice are usually determined using empirically determined approximate formulae (Andreasen or Fuller distribution curves) which take into account the morphology of the individual particles. 

An oxide of aluminum is formed by the reaction of 4.151 g of aluminum with 3.692 g of oxygen. Calculate the empirical formula for this compound. 

We want to determine the empirical formula for the aluminum oxide, AlxOy. That is, we want to solve for x and y. 

So the empirical formula of aluminum oxide is AI2O3, and the reaction is... 

Because aluminum tends to form the cation (Al ) and oxygen the anion (0 ) in ionic compounds, the transfer of electrons is fiom Al to O. There are three valence electrons in each Al atom each O atom needs two electrons to form the ion, which is isoelectronic with neon. Thus, the simplest neutralizing ratio of AP to is 2 3 two AP" ions have a total charge of +6, and three ions have a total charge of -6. So the empirical formula of aluminum oxide is AI2O3, and the reaction is... 

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