Question

A hydrocarbon is a compound that contains mostly carbon and hydrogen. Calculate the percent composition (by mass) of the following hydrocarbon: C 7 H 16 .
Enter the percentages of carbon and hydrogen numerically to four significant figures, separated by commas.

Answer 1

C7H16, where C=12.01, and H=1.01, so the weight of the molecule would be 7(12.01)+16(1.01), or 100.23. The percentage of carbon would be found by ((7*12.01)/100.23)*100=83.88% Carbon
((16*1.01)/100.23)*100=16.12% Hydrogen