Propene may be obtained by the dehydration of

Options

A. ethyl alcohol
B. methyl alcohol
C. propyl alcohol
D. isopropyl alcohol

Answer

To determine which alcohols can be dehydrated to form propene, we will analyze each option provided in the question. The dehydration process involves the removal of a water molecule (H2O) from the alcohol, typically facilitated by a strong acid like concentrated sulfuric acid (H2SO4).

### Step-by-Step Solution:

1. **Identify the Alcohols**: The options given are:
- Ethyl alcohol (C2H5OH)
- Methyl alcohol (CH3OH)
- Propyl alcohol (C3H7OH)
- Isopropyl alcohol (C3H8O)

2. **Understand Dehydration**: Dehydration involves the elimination of the hydroxyl group (OH) from the alpha carbon and a hydrogen atom from the beta carbon, resulting in the formation of an alkene.

3. **Analyze Ethyl Alcohol (C2H5OH)**:
- Structure: CH3-CH2-OH
- Dehydration: Remove OH from the alpha carbon (C2) and H from the beta carbon (C1).
- Result: CH2=CH2 (Ethylene) + H2O
- Conclusion: Ethyl alcohol does not yield propene.

4. **Analyze Methyl Alcohol (CH3OH)**:
- Structure: CH3-OH
- Dehydration: No beta carbon is present.
- Conclusion: No dehydration reaction occurs; thus, it cannot yield propene.

5. **Analyze Propyl Alcohol (C3H7OH)**:
- Structure: CH3-CH2-CH2-OH
- Dehydration: Remove OH from the alpha carbon (C3) and H from the beta carbon (C2).
- Result: CH3-CH=CH2 (Propene) + H2O
- Conclusion: Propyl alcohol can yield propene.

6. **Analyze Isopropyl Alcohol (C3H8O)**:
- Structure: CH3-CHOH-CH3
- Dehydration: Remove OH from the alpha carbon (C2) and H from either beta carbon (C1 or C3).
- Result: CH3-CH=CH2 (Propene) + H2O
- Conclusion: Isopropyl alcohol can also yield propene.

### Final Answer:
Propene may be obtained by the dehydration of:
- Propyl alcohol (C3H7OH)
- Isopropyl alcohol (C3H8O)