Question

guided practice
which chemical formula represents a hydrocarbon compound?
a. $c_8h_{18}$
b. $c_6h_{12}o_6$
c. $co_2$
d. $nh_4$

Explanation:

A hydrocarbon is a compound composed exclusively of carbon and hydrogen atoms. We analyze each option:

• Option A: $\text{C}_8\text{H}_{18}$ contains only carbon and hydrogen, fitting the hydrocarbon definition.
• Option B: $\text{C}_6\text{H}_{12}\text{O}_6$ includes oxygen, so it is a carbohydrate, not a hydrocarbon.
• Option C: $\text{CO}_2$ includes oxygen, it is an inorganic carbon compound, not a hydrocarbon.
• Option D: $\text{NH}_4$ contains nitrogen and hydrogen, it is an ammonium cation, not a hydrocarbon.

Answer:

A. $\text{C}_8\text{H}_{18}$