Label each hydrogen atom in the following compounds as primary (1°), secondary (2°), or tertiary (3°).
(a) CH₃CH₂CH(CH₃)₂
(b) (CH3)₃CCH₂CH₃

Verified step by step guidance

1. Step 1: Understand the concept of primary, secondary, and tertiary hydrogen atoms. Primary hydrogens are attached to a carbon that is bonded to only one other carbon. Secondary hydrogens are attached to a carbon bonded to two other carbons. Tertiary hydrogens are attached to a carbon bonded to three other carbons.
2. Step 2: Analyze compound a, CH3CH2CH(CH3)2. Start by identifying the types of carbon atoms present. The first carbon (CH3-) is bonded to one other carbon, making it a primary carbon. The second carbon (CH2-) is bonded to two other carbons, making it a secondary carbon. The third carbon (CH-) is bonded to three other carbons, making it a tertiary carbon.
3. Step 3: Label the hydrogen atoms in compound a. The hydrogens on the CH3 group are primary hydrogens. The hydrogens on the CH2 group are secondary hydrogens. The hydrogen on the CH group is a tertiary hydrogen.
4. Step 4: Analyze compound b, (CH3)3CCH2CH3. Identify the types of carbon atoms. The first carbon (C-) is bonded to three other carbons, making it a tertiary carbon. The second carbon (CH2-) is bonded to two other carbons, making it a secondary carbon. The third carbon (CH3-) is bonded to one other carbon, making it a primary carbon.
5. Step 5: Label the hydrogen atoms in compound b. The hydrogens on the CH3 groups attached to the tertiary carbon are primary hydrogens. The hydrogens on the CH2 group are secondary hydrogens. The hydrogens on the CH3 group at the end are primary hydrogens.

Key Concepts

Hydrogen Atom Classification

In organic chemistry, hydrogen atoms are classified based on the carbon atom they are attached to. A primary (1°) hydrogen is attached to a primary carbon, which is bonded to only one other carbon. A secondary (2°) hydrogen is attached to a secondary carbon, bonded to two other carbons, and a tertiary (3°) hydrogen is attached to a tertiary carbon, bonded to three other carbons.

Carbon Atom Classification

Carbon atoms are classified as primary, secondary, or tertiary based on the number of other carbon atoms they are directly bonded to. A primary carbon is bonded to one other carbon, a secondary carbon to two, and a tertiary carbon to three. This classification helps in determining the type of hydrogen atoms attached to them.

Structural Formula Analysis

Analyzing the structural formula of a compound involves identifying the connectivity of atoms within the molecule. This includes determining which carbon atoms are primary, secondary, or tertiary, and subsequently classifying the hydrogen atoms attached to them. Understanding the structure is crucial for accurate classification and understanding of molecular properties.