## Step 1: Identify Equivalent Hydrogens Let's analyze the molecule for chemically equivalent hydrogens (protons). Hydrogens that are in the same environment (same connectivity and symmetry) will give the same NMR signal. - The molecule is 1,1-dichloropentane (Cl₂CH–CH₂–CH₂–CH₂–CH₃). - We need to check each type of hydrogen: - **CH₃ group** at the end: All 3 hydrogens are equivalent. - **CH₂ groups**: Each one may be in a different environment. - **CH group** bonded to two Cl: This H is unique. **Explanation:** Each unique environment gives a different NMR signal. Let's count the types: 1. CH₃ hydrogens (end of chain) 2. Terminal CH₂ next to CH₃ 3. Middle CH₂ 4. CH₂ next to CCl₂ 5. Single H on CCl₂ So, there are **5 different types** of hydrogens. --- ## Step 2: Highlight Equivalent Hydrogens ### Top Molecule The red hydrogen is on the CCl₂ carbon. This position is unique because it's the only hydrogen on that carbon (the other positions are occupied by Cl atoms). **No additional H atoms** will contribute to the same signal as the red H. - **Check the box:** No additional H atoms to highlight in top molecule. ### Bottom Molecule The red hydrogen is on the CH₂ group next to the CCl₂ carbon. The two hydrogens on this CH₂ group are equivalent because they are bonded to the same carbon, which is attached to CCl₂ and another CH₂ group. - **Highlight the other H** on this same CH₂ group (beside the already red one). --- ## Final Answer - **Number of signals in the ¹H NMR spectrum:** **5** - **Top molecule:** - No additional H atoms to highlight (check the box). - **Bottom molecule:** - Highlight the other H on the same CH₂ group as the red H.