Question

To what does the root name for a branched hydrocarbon correspond?

Short answer

The root name for a branched hydrocarbon corresponds to the longest continuous chain of carbon atoms (parent chain) in the molecule, determining the family of hydrocarbons to which the compound belongs. It is based on the number of carbon atoms in the parent chain and follows the prefix indicating the number of carbons (meth-, eth-, prop-, but-, etc.) and the suffix "-ane" for alkanes.

Step-by-step solution

Understanding Branched Hydrocarbons

A branched hydrocarbon is an organic compound consisting primarily of carbon and hydrogen atoms, with a structure that includes at least one main chain of carbon atoms and one or more branches (alkyl groups) connected to the main chain. These alkyl groups can be attached at any position along the carbon chain.

Understanding the Naming Convention for Branched Hydrocarbons

In the naming of branched hydrocarbons, the IUPAC (International Union of Pure and Applied Chemistry) nomenclature system is used to ensure consistent and accurate communication among scientists worldwide. The IUPAC system provides a set of rules and guidelines for naming organic compounds based on their molecular structures.

Breaking Down the Naming Convention

When naming a branched hydrocarbon, the name is composed of three main parts: 1. The root (or base) name 2. The names of the branching alkyl groups 3. The position of the branching alkyl groups on the main carbon chain The root (or base) name corresponds to the longest continuous chain of carbon atoms (called the parent chain) in the molecule, which determines the family of hydrocarbons to which the compound belongs. The root name is based on the number of carbon atoms present in the parent chain, following the prefix indicating the number of carbons (meth-, eth-, prop-, but-, etc.) and the suffix "-ane" for alkanes. For example, if the parent chain contains 4 carbon atoms, the root name is "butane."

Identifying the Root Name for a Branched Hydrocarbon Example

Let's look at an example of a branched hydrocarbon: CH3−CH(CH3)−CH2−CH3 1. Identify the longest continuous chain of carbon atoms: In this case, the longest chain contains 4 carbon atoms. 2. Determine the root name based on the number of carbon atoms: With 4 carbons in the parent chain, the root name is "butane." 3. Name any branching alkyl groups and their positions: There is one methyl group (CH3) at the second carbon atom in the main chain. To indicate this, add a number reflecting the position (2), a hyphen, and the branching group name: "2-methyl." 4. Combine the branching information with the root name to form the compound's complete name: "2-methylbutane"

Conclusion

The root name for a branched hydrocarbon corresponds to the longest continuous chain of carbon atoms in the molecule, which determines the family of hydrocarbons to which the compound belongs. The root name is based on the number of carbon atoms present in the parent chain and forms an essential part of the IUPAC nomenclature used for consistent and accurate communication among scientists.