# Lewis Structures for 2-Methoxy-2-methylpropane and 2-Methylpropan-2-ol Let's draw the Lewis structures for **2-methoxy-2-methylpropane** and **2-methylpropan-2-ol** step by step. --- ## 1. 2-Methoxy-2-methylpropane ### Step 1: Determine the Molecular Formula - **2-methoxy-2-methylpropane** - The parent chain is propane (3 carbons). - At carbon 2: both a methyl group (-CH₃) and a methoxy group (-OCH₃). - Structure: ``` CH₃ | CH₃–C–O–CH₃ | CH₃ ``` - Molecular formula: C₅H₁₂O ### Step 2: Identify the Atoms and Groups - Central carbon (C2) has: - 3 methyl groups (–CH₃) - 1 methoxy group (–OCH₃) ### Step 3: Arrange the Atoms - Place the central carbon with three methyls and one methoxy: ``` CH₃ | CH₃–C–O–CH₃ | CH₃ ``` ### Step 4: Add Bonds and Lone Pairs - Each C forms 4 bonds. - O forms 2 bonds, with 2 lone pairs. ### Step 5: Draw the Lewis Structure ```markdown H H H | | | H–C–C–O–C–H | | | H C H | | H H ``` Or, showing all atoms and lone pairs on oxygen: ``` CH₃ | CH₃ — C — O — CH₃ | CH₃ Where: - Each line is a single bond. - The oxygen atom (O) has two lone pairs. ``` **Lone pairs on oxygen:** :O: (with two lone pairs, i.e., 4 dots) So, at the O atom, draw two pairs of dots. --- ## 2. 2-Methylpropan-2-ol ### Step 1: Determine the Molecular Formula - **2-methylpropan-2-ol** - Propane backbone, methyl group at C2, OH at C2. - Structure: ``` CH₃ | CH₃–C–OH | CH₃ ``` - Molecular formula: C₄H₁₀O ### Step 2: Identify the Atoms and Groups - Central carbon (C2) has: - 3 methyl groups (–CH₃) - 1 hydroxyl group (–OH) ### Step 3: Arrange the Atoms - Place the central carbon with three methyl groups and one OH: ``` CH₃ | CH₃–C–OH | CH₃ ``` ### Step 4: Add Bonds and Lone Pairs - Each C forms 4 bonds. - O forms 2 bonds (to H and C), with 2 lone pairs. ### Step 5: Draw the Lewis Structure ```markdown H H H | | | H–C–C–O–H | | H C | | H H ``` Or, showing all atoms and lone pairs on oxygen: ``` CH₃ | CH₃ — C — OH | CH₃ Where: - Each line is a single bond. - The oxygen atom (O) in OH has two lone pairs. ``` **Lone pairs on oxygen:** :O: (with two lone pairs, i.e., 4 dots) So, at the O atom, draw two pairs of dots. --- ## Final Answers ### 2-Methoxy-2-methylpropane (C₅H₁₂O) ``` CH₃ | CH₃–C–O–CH₃ | CH₃ ``` - Oxygen has two lone pairs. --- ### 2-Methylpropan-2-ol (C₄H₁₀O) ``` CH₃ | CH₃–C–OH | CH₃ ``` - Oxygen in –OH has two lone pairs. --- ## Summary Table | Compound | Structure | Functional Group | |------------------------------|---------------------------------------------------------|--------------------| | 2-methoxy-2-methylpropane | CH₃–C(CH₃)₂–O–CH₃ | Ether | | 2-methylpropan-2-ol | CH₃–C(CH₃)₂–OH | Alcohol | **Tip:** Always ensure oxygen atoms have two lone pairs in your Lewis structures.