Including cyclic compounds, how many possible isomers exist for C₄H₈? A)2 B)4 C)5 D)6 E)7

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Quizplus · Accepted Answer

Since there are 5 carbon atoms, there are 5 possible arrangements for the linear chain. Each carbon can be either part of a double bond or a single bond. Therefore, there are 2^5 = 32 possible isomers for the linear chain. However, the molecule also contains two sulfur atoms, which can either both be in a cyclic ring, both be outside of the ring, or one be in the ring and one be outside of the ring. Each of these possibilities adds an additional set of isomers. The first possibility (both sulfur atoms in a ring) gives rise to 2 isomers (cis and trans). The second possibility (both sulfur atoms outside of the ring) gives rise to 1 isomer. The third possibility (one sulfur atom in the ring and one outside of the ring) gives rise to 3 isomers (depending on which sulfur atom is in the ring and which is outside, and whether the ring is cis or trans). Therefore, the total number of possible isomers is 32 x 2 x 1 x 3 = 192, which includes both linear and cyclic compounds.

Including Cyclic Compounds, How Many Possible Isomers Exist for C4H8

Including Cyclic Compounds, How Many Possible Isomers Exist for C₄H₈