# Determine the empirical formula of an oxide of silicon from the following: Mass of crucible = 18.20 g, mass of crucible + silicon = 18.48 g and mass of crucible + oxide of silicon = 18.80 g. The mass of the crucible is given as 18.2 g. The mass of the crucible + mass of the silicon is 18.48 g.

This gives the mass of the silicon alone as 18.48 - 18.20 = 0.28 g.

The mass of the crucible and the silicon oxide is 18.80 g

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The mass of the crucible is given as 18.2 g. The mass of the crucible + mass of the silicon is 18.48 g.

This gives the mass of the silicon alone as 18.48 - 18.20 = 0.28 g.

The mass of the crucible and the silicon oxide is 18.80 g

This gives the mass of the silicon oxide as 18.8 - 18.2 = 0.6 g

So we have 0.28 g of silicon reacting with 0.6 - 0.28 = 0.32 g of oxygen to give the silicon oxide.

The ratio of the molar mass of oxygen to the molar mass of silicon is 16 : 28. From what we have found above, that 0.32 g of oxygen reacts with .28 g of silicon, we can say that the molecular formula of the silicon oxide is SiO2.

The required empirical formula of the silicon oxide is SiO2.

Approved by eNotes Editorial Team