The following is not an endothermic reactions:

Options

A. Combustion of methane
B. Decomposition of water
C. Dehydrogenation of enthane of diamond
D. Conversion of graphite to diamond

Explanation

To determine which of the following reactions is not an endothermic reaction, we first need to understand what endothermic reactions are. Endothermic reactions are those that absorb heat from their surroundings. Conversely, exothermic reactions release heat.

Let's analyze each option provided:

1. **Combustion of Methane**:
- The combustion of methane (CH₄) is a reaction where methane reacts with oxygen to produce carbon dioxide and water, releasing heat in the process.
- This is an exothermic reaction because it releases energy (heat) to the surroundings.

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