20.2/20.2 = 1.000
6.64/20.2 = 0.329
So the empirical formula is
C3H20
calculate the empirical formula: 79.8%C and 20.2%H. what os the formula
Take a 100 g sample. That will give you
79.8 g C
20.2 g H.
convert g to mols. mols = g/molar mass.
79.8/12.01 = 6.64
20.2/1 = 20.2
This gives the formula of
C6.64H20.2
However, we know from Dalton's theory that atoms combine in the ratio of small whole numbers. So convert the above values into small whole numbers. Hint: Divide the smaller number by itself; that will make it be 1.000. Then divide the other number by the same value. That is an easy way to convert to small whole numbers.
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