Empirical Formulas
With the help of a pocket calculator, you can determine empirical formulas.
In coal-burning countries, the major air pollutant is a compound containing
only sulfur and oxygen. Analysis of a 2.156 g sample of this gas showed that it
contained 1.080 g of S and 1.076 g of O. What is the empirical formula of
this compound?
Solution:
-Enter S+O and SUBMIT it.
-Enter 1.080 in the grams column of S and
1.076 in the grams column of O and hit the STEPPER (CALCULATE)
button.
-The moles column gives the subscripts of the various elements
in the empirical formula but they are not in integer form.
-We see that S has the smallest mole value, 0.033676 so we take
a pocket calculator and divide every mole value by that number.
-Putting the results on a sheet of paper, we see S now has
a subscript of 1 and O has a subscript that rounds off to 2.
-We conclude that the empirical formula is SO2
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