Answer:
Number 1 will be in the lowest molar quantity b/c formation of 1st order products are more difficult to form than secondary (#2) or tertiary (#3) substitution products.
Explanation:
In general, if a substitution occurs such that it is attached to a carbon that's attached to only one carbon, it is referred to as a primary carbon substitution. If a substitution occurs on a carbon that is attached to two (2) carbons, it is a secondary carbon substitution. Finally, if a substitution occurs such that it is attached to a carbon that's attached to three (3) carbons it is a tertiary substitution. Typically, primary substitution products follow an Sn2 type reaction pathway. Such requires the formation of only one intermediate that difficult to form as compared to 2° or 3° intermediates. Once formed, however, they will be very unstable and proceeds to product very quickly. Such produce very low product yield. The intermediates for 2° and 3° form more easily and are more stable in the reaction environments. An example is tertiary butyl halogens (e.g., t-butyl chloride) follow and Sn1 type reaction pathway forming a tertiary carbocation which then reacts with a nucleophile of choice and forms much higher yields than the 1° carbon substitution reactions. Suggest reviewing Sn2 and Sn1 substitution reactions.
