a sample of a compound with a mass of 0.4168g is extracted from a plant. Decompostion of this sample produces 0.1667g of carbon, 0.2223g oxygen, and the remainder is hydrogen. What is the percentage compostion (by mass) of the compound?

Answer 1

.1667/.4168 = .400 is Carbon = 40%

.2223/.4168 = .533 is Oxygen = 53.3 %

so
.067 is H = 6.7 %