A 143.1 g sample of a compound contains 53.4 g of carbon, 6.9 g of hydrogen, 43 g of nitrogen, and some amount of oxygen. What is the mass percent of oxygen in the compound?

1 Answer
Aug 24, 2016

27.8% oxygen

Explanation:

Let me start by writing a simple equation

#143.1=53.4+6.9+43+x#

x stands for amount of oxygen in grams

When you solve this equation, #x=143.1-(53.4+6.9+43)#

#x=143.1-103.3#

# x=39.8 g#

Now in percent form

Mass percent of oxygen #100*39.8/143.1#

#=27.8%#