Which of the following resonance structure for propenal is more stable ?

Explanation

To determine which resonance structure of propenal is more stable, we need to analyze the two given resonance structures based on several stability criteria. Here’s a step-by-step solution:

### Step 1: Identify the Resonance Structures
We have two resonance structures for propenal:
1. Structure A: CH2=CH-CHO (with a double bond between the first two carbons and a carbonyl group at the end)
2. Structure B: CH2^+-CH=CH-O^- (with a positive charge on the first carbon and a negative charge on the oxygen)

### Step 2: Check the Octet Rule
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