The number of different chain isomers for C7H16 is _____.
Answer: 9
Solution
The number of chain (skeletal) isomers of a saturated hydrocarbon C7H16 (heptane) is the number of distinct carbon skeletons: n-heptane, the three methylhexanes (2-, 3-methyl), the ethylpentane, the dimethylpentanes and trimethylbutane — 9 in total. Answer: 9.Structure (i)Structure (ii)Structure (iii)Structure (iv)Structure (v)Structure (vi)Structure (vii)Structure (viii)Structure (ix)