How would you calculate the percentage by mass of oxygen in a compound?

1 Answer
Nov 18, 2016

#"%Oxygen"="Mass of oxygen"/"Formula mass of compound"xx100%#

Explanation:

Let's try this with #"potassium permangante, " KMnO_4#, whose formula mass is #158.03*g*mol^-1#.

#"% oxygen "= (4xx15.999*g*mol^-1)/(158.03*g*mol^-1)xx100%~=40%#