Nuclear fission and fusion are examples of conversion of mass into energy. Is strictly speaking mass converted into energy even in an exothermic chemical reaction ?

Explanation

**Step-by-Step Solution:**

1. **Understanding Nuclear Fission and Fusion:**
- Nuclear fission and fusion are processes where a significant amount of energy is released due to the conversion of mass into energy, as described by Einstein's equation \(E=mc^2\). In these processes, a small amount of mass is lost, which is converted into a large amount of energy.

2. **Defining Exothermic Reactions:**
- An exothermic reaction is a chemical reaction that releases energy in the form of heat. In these reactions, the products have lower energy than the reactants, and the difference in energy is released as heat.

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