Question

which of the following compounds is identical to the one shown below?

Explanation:

Step1: Analyze the given compound

The given compound is a straight - chain butane ($C_4H_{10}$) with the structure $H - C - C - C - C - H$ where each carbon is bonded to appropriate hydrogens to satisfy the valency of 4.

Step2: Analyze each option

The first option is a branched - chain compound (2 - methylpropane). The second option has a double bond (an alkene). The third option is a branched - chain compound (2 - methylbutane). The fourth option is a three - carbon chain compound. The fifth option $CH_3CH_2CH_2CH_2CH_3$ is pentane. The correct structure that is identical to the given four - carbon straight - chain compound is the one with the same connectivity and number of atoms.

Answer:

The compound that is identical to the given one is the straight - chain butane structure among the options (the original structure itself as no other option matches exactly in terms of carbon - carbon and carbon - hydrogen connectivity and number of atoms). But if we assume the last option is a mis - type and should be $CH_3CH_2CH_2CH_3$ (butane), then that is the correct answer.