Question

The prefix valer- is used for generally used for naming aldehydes with how many carbon atoms in the structure?

(a) 3

(b) 4

(c) 5

(d) 6

The question was posed to me by my college professor while I was bunking the class.

I would like to ask this question from Nomenclature and Structure of Carbonyl Groups topic in chapter Aldehydes, Ketones and Carboxylic Acids of Chemistry – Class 12

Answer 1

Right answer is (c) 5

To explain I would say: When aldehydes have exactly 5 carbon atoms in their structure, including the carbonyl group and any substituted groups, the aldehyde is given the prefix valer- in the common naming system. For example, pentanal is named as n-Valeraldehyde.