Question

A 0.2385 gram sample of a compound composed of iron and sulfur was analyzed and

determined to contain 63.52% iron and 36.48% sulfur. What is the empirical formula of
this compound?

Answer 1

Step-by-step explanation:

To find the empirical formula of the compound, we need to determine the smallest whole number ratio of atoms in the compound. We can do this by assuming a 100 gram sample of the compound, which allows us to convert the percentage composition into actual masses of each element.

Assuming a 100 gram sample, the mass of iron in the compound would be:

mass of iron = 63.52 g

The mass of sulfur would be:

mass of sulfur = 36.48 g

Now we can calculate the number of moles of each element using their respective atomic masses:

moles of iron = 63.52 g / 55.85 g/mol = 1.136 mol

moles of sulfur = 36.48 g / 32.06 g/mol = 1.138 mol

The ratio of iron to sulfur in the compound can be expressed as:

iron:sulfur = 1.136 mol : 1.138 mol

To obtain whole number ratios, we can divide both values by the smaller value:

iron:sulfur = 0.997 : 1

This means that the empirical formula of the compound is FeS.