What is the empirical formula of a compound containing 83% potassium and 17% oxygen?

1 Answer
Mar 4, 2016



The following method serves for every compound:

In each 100 g of the compound you have 83 g of potassium and 17 g of oxygen.

To determine the empiriacal formula you have to pass these masses into mols

#83/39.1=2.12 mol K# and #17/16=1.06 mol O#

Now divide all the numbers by the smallest you have obatined:

#2.12/1.06=2.0 K# and #1.06/1.06=1 mol O#

So it is #K_2O#

At this stage you can have numbers that are not integer. In this case you would have to multiply the resulsts by an integer in a way the final result is a proportion of integers:

Imagine you had obtained 1.5 K for 1 O. You just had to multiply by 2 to get the integer proportion of 3:1.