gas oil vs hydrocarbon

gas oil and hydrocarbon both are nouns.

Word	Noun	Adjective	Verb	Adverb
gas oil	Yes	No	No	No
hydrocarbon	Yes	No	No	No

As nouns, hydrocarbon is a hypernym of gas oil; that is, hydrocarbon is a word with a broader meaning than gas oil:

gas oil: an oil formed through distillation of petroleum of intermediate boiling range and viscosity
hydrocarbon: an organic compound containing only carbon and hydrogen

Other hypernyms of gas oil include fuel oil, heating oil.

gas oil (noun)	hydrocarbon (noun)
an oil formed through distillation of petroleum of intermediate boiling range and viscosity	an organic compound containing only carbon and hydrogen