Question 1

Choose the letter of the correct name for each structure.

CH3CH2CH2CH2CH3

pentane

propane

hexane

Answer : The name of the given hydrocarbon is, pentane.

Explanation:

The basic rules for naming of organic compounds are:

First select the longest possible carbon chain. For the number of carbon atom, we add prefix as 'meth' for 1, 'eth' for 2, 'prop' for 3, 'but' for 4, 'pent' for 5, 'hex' for 6, 'sept' for 7, 'oct' for 8, 'nona' for 9 and 'deca' for 10. A suffix '-ane' is added at the end of the name of alkane. If two of more similar alkyl groups are present, then the words 'di', 'tri' 'tetra' and so on are used to specify the number of times these alkyl groups appear in the chain.

In the given hydrocarbon, the longest possible carbon chain number is 5 that means we add prefix 'pent' and suffix '-ane'. So, the name of given hydrocarbon will be, pentane.

Hence, the correct option is, pentane.