The difference of energy between the actual structure of molecule and that of the most stable
contributing structure is called……………

Explanation

To solve the question, we need to identify the term that describes the difference in energy between the actual structure of a molecule and its most stable contributing structure. Here’s a step-by-step breakdown of the solution:

### Step-by-Step Solution:

1. **Understand the Concept of Resonance**:
- In chemistry, resonance refers to the way in which a molecule can be represented by two or more valid Lewis structures (called resonance structures) that differ only in the arrangement of electrons.

2. **Identify the Actual Structure**:
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