The most suitable reagent for the conversion of
Propanol to Propanal is
a. KMnO4
b.K2Cr2O7
c.CrO3
d. PCC

Explanation

To convert propanol (a primary alcohol) to propanal (an aldehyde), we need to choose the most suitable reagent from the given options. Let's analyze each option step by step.

### Step 1: Identify the structure of propanol and propanal
- Propanol (C3H8O) is a primary alcohol with the structure CH3-CH2-CH2OH.
- Propanal (C3H6O) is an aldehyde with the structure CH3-CH2-CHO.

### Step 2: Understand the oxidation process
- The conversion of a primary alcohol to an aldehyde involves oxidation.
- A suitable oxidizing agent should be able to oxidize propanol to propanal without further oxidizing it to a carboxylic acid.

### Step 3: Evaluate the reagents
1. **KMnO4 (Potassium permanganate)**:
- This is a strong oxidizing agent. It can oxidize primary alcohols to carboxylic acids. Therefore, it would convert propanol to propanoic acid instead of stopping at propanal.

2. **K2Cr2O7 (Potassium dichromate)**:
- This is also a strong oxidizing agent. Similar to KMnO4, it would oxidize propanol to propanoic acid, not stopping at the aldehyde stage.

3. **CrO3 (Chromic acid)**:
- This is another strong oxidizing agent that would oxidize propanol to propanoic acid, bypassing the aldehyde stage.

4. **PCC (Pyridinium chlorochromate)**:
- This is a milder oxidizing agent specifically designed to oxidize primary alcohols to aldehydes without further oxidation to carboxylic acids. It effectively stops the reaction at the aldehyde stage.

### Step 4: Conclusion
- Based on the analysis, the most suitable reagent for the conversion of propanol to propanal is **PCC (Pyridinium chlorochromate)**.

### Final Answer:
**d. PCC**

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