CHEMISTRY

JAMB 2009 - Question 49

Chemistry 2009 JAMB Past Questions - Question 49: The simplest branched-chain hydrocarbon is

Choose the correct answers from the options given.
The simplest branched-chain hydrocarbon is
A:
B:
C:
D:
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Correct Answer

D

Explanation

The simplest branched-chain hydrocarbon is **isobutane**, also known as 2-methylpropane. It has the molecular formula **C4H10** and its structure consists of a three-carbon chain with a methyl group (-CH3) attached to the middle carbon.

Here's why:

* **Branched-chain:** Unlike its straight-chain counterpart, butane (CH3CH2CH2CH3), isobutane has a methyl group branching off the main chain, making it a branched-chain hydrocarbon.
* **Simplest:** Among other branched-chain hydrocarbons with the same formula like methylpropane (CH3CHCH3), isobutane has the least complex branching pattern, with just one methyl group attached to the central carbon.

Therefore, isobutane fulfills the criteria of being both a branched-chain and the simplest example with the formula C4H10.