Question

What is the empirical formula? A compound is used to treat iron deficiency in people. It contains 36.76% iron, 21.11% sulfur, and 42.13% oxygen. The empirical formula is FeSO. Reset Next

Answer 1

Empirical Formula is Fe1S1O4

(the numbers are suppose to be subscript)

Answer 2

Answer: $FeSO_4$

Solution : Given,

If percentage are given then we are taking total mass is 100 grams.

So, the mass of each element is equal to the percentage given.

Mass of Fe = 36.76 g

Mass of S = 21.11 g

Mass of O = 42.13 g

Step 1 : convert given masses into moles.

Moles of Fe =$\frac{\text{ given mass of Fe}}{\text{ molar mass of Fe}}= \frac{36.76g}{56g/mole}=0.65moles$

Moles of S = \frac{\text{ given mass of S}}{\text{ molar mass of S}}= \frac{21.11g}{32g/mole}=0.65moles

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Moles of O = \frac{\text{ given mass of O}}{\text{ molar mass of O}}= \frac{42.13g}{16g/mole}=2.63[/tex]

Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.

For Fe = $\frac{0.65}{0.65}=1$

For S = $\frac{0.65}{0.65}=1$

For O =$\frac{2.63}{0.65}=4$

The ratio of Fe : S : O= 1 : 1 : 4

Hence the empirical formula is $Fe_{1}S_{1}O_4$