Will Medal And Fan

A compound weighing 115 g contains 68.3 g of carbon, 13.2 g of hydrogen, 15.9 g of nitrogen, and some amount of oxygen. What is the mass percent of oxygen in the compound?

11.48%

15.30%

13.83%

13.91%

Question

Will Medal And Fan

A compound weighing 115 g contains 68.3 g of carbon, 13.2 g of hydrogen, 15.9 g of nitrogen, and some amount of oxygen. What is the mass percent of oxygen in the compound?

11.48%

15.30%

13.83%

13.91%

jfraser · Answer

You know what the whole sample weighs, and you know what $three$ of the $four$ pieces weigh. How much does the fourth piece weigh?