How do you determine an empirical formula?

1 Answer
Sep 28, 2016

See explanation below:


The empirical formula is essentially a compound in which the atom-atom ratio of different elements is in the smallest whole number ratio. This doesn't necessarily need to be the actual chemical formula of the compound.

To determine an emperical formula from a compound, all you'd need to do is check the amounts of each atom present, and see if you can simplify the ratio of atoms.

So for example, consider the chemical formula for glucose:


The empirical formula of this is would be

#CH_2O#, because the ratio of Carbon Atoms to Hydrogen Atoms to Oxygen atoms is 1:2:1. You could get this answer by noticing that all the numbers of atoms in #C_6H_12O_6# are divisible by 6, and then divide them by 6.

There are more complicated problems involving empirical formula. To see some of those, you can watch the two videos below:

  1. Khan Academy

  2. chemistNATE

Hope that helps :)