Final answer:
To find the empirical formula for silicon oxide, subtract the mass of silicon from the total mass to find the mass of oxygen, then convert the masses to moles and find the simplest whole number ratio between them.
Step-by-step explanation:
To determine the empirical formula of an oxide of silicon that contains 2.50 g of silicon and has a total mass of 5.36 g, we must first find the mass of oxygen in the compound by subtracting the mass of silicon from the total mass of the compound:
Mass of oxygen = total mass – mass of silicon = 5.36 g – 2.50 g = 2.86 g
Next, we calculate the moles of each element using the atomic masses (silicon = 28.09 g/mol and oxygen = 16.00 g/mol):
Moles of silicon = mass of silicon / atomic mass of silicon = 2.50 g / 28.09 g/mol
Moles of oxygen = mass of oxygen / atomic mass of oxygen = 2.86 g / 16.00 g/mol
After calculating the moles, we divide both by the smallest number of moles to find the ratio:
Ratio silicon: Ratio oxygen = Moles of silicon / Smallest number of moles : Moles of oxygen / Smallest number of moles
If the ratio does not yield whole numbers, we multiply by the smallest possible factor to obtain whole numbers for both elements, which gives us the empirical formula of the silicon oxide.