Students were shown the structure of an alkane and were asked to write the IUPAC name of the alkane for an exam. Of the following answers that were given, which answer corresponds to the correct IUPAC name of a compound?
A) 2-ethyl-2-methylbutane
B) 2,2-dimethylbutane
C) 2,2-diethylbutane
D) none of these

Question

Quizplus · Accepted Answer

The term "alkane" refers to a type of hydrocarbon with only single bonds between carbon atoms. The IUPAC name of an alkane comes from the number of carbon atoms in the longest continuous chain and any branches or substituents on that chain. In this case, the alkane has a chain of four carbon atoms. Choice B, 2,2-dimethylbutane, correctly indicates that there are two methyl groups (CH3) attached to the second carbon atom on the chain, making it a "2,2" position. Choices A and C both have the correct number of carbons in the longest chain and the correct number of substituents, but they place those substituents on different carbon atoms, which would give them different names. Choice D is incorrect because there is a correct IUPAC name among the options.

Students Were Shown the Structure of an Alkane and Were