Question

Suppose an alkane had 8 carbon atoms. How many hydrogen atoms would it have? a. 18 atoms c. 10 atoms b. 16 atoms d. 12 atoms

Answer 1

Answer;

A. 18 hydrogen atoms

Explanation;

• Alkanes are group of hydrocarbon that are saturated. They are saturated in the sense that each carbon atom has maximum number of hydrogen atoms.
• The homologous series of alkanes has a general formula of CₓH₂ₓ₊₂.
• Therefore, an alkane with 8 carbons will have; (2×8) +2 = 18 hydrogen atoms. Thus, the formula of the hyrocarbon will be; C₈H₁₈.

Answer 2

In alkane, number of hydrogen atom = 2n + 2
Where, n = number of carbon atoms

So, it would be: 2(8)+2 = 16+2 = 18

In short, Your Answer would be Option A

Hope this helps!