Which of the following alkyl chloride will have the lowest boiling point?
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To determine the lowest boiling point, consider the size of the molecule and the types of intermolecular forces present. Small molecules like CH$_3$Cl have lower boiling points than larger, more complex molecules.
Step 1: Understand factors influencing the boiling point of alkyl halides.
- Boiling point is determined by molecular weight, degree of branching, and intermolecular forces, particularly van der Waals forces.
- Generally, increased molecular mass and reduced branching lead to higher boiling points.
Step 2: Analyze the provided compounds:
Option 1: CH3CH2Br — Ethyl bromide (Note: This is an alkyl bromide, not an alkyl chloride. Bromine's higher atomic mass compared to chlorine results in a higher boiling point).
Option 2: C6H5CH2Cl — Benzyl chloride (Characterized by a bulky structure and higher molar mass).
Option 3: (CH3)2CHCl — Isopropyl chloride (Features a branched structure, leading to a moderate boiling point).
Option 4: CH3Cl — Methyl chloride (The smallest molecule with the lowest molar mass and minimal van der Waals interaction).
Step 3: Identify the compound with the lowest boiling point.
- Methyl chloride (CH3Cl) possesses the lowest molecular weight and exhibits the least polarizability.
- Consequently, it experiences the weakest intermolecular forces, resulting in the lowest boiling point.
