Concept:The molecular formula
C5H12 represents saturated acyclic alkanes with five carbon atoms.
Their isomers arise from different arrangements of the carbon skeleton.
Explanation:Write all possible straight and branched chains with five carbon atoms.
First, the straight-chain structure is pentane.
Then, move one carbon atom to form a branch on a four-carbon chain: this gives 2-methylbutane.
Next, arrange the skeleton with a three-carbon main chain and two methyl branches: this gives 2,2-dimethylpropane.
No other unique skeletons can be drawn for
C5H12.
Thus, it forms three structural isomers.
Answer:Option C. Three.