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Carbon of the coal can combine with oxyg...

Carbon of the coal can combine with oxygen of air to form CO, `CO_(2)` etc. (i.e., `DeltaG` is - ve are the reaction is thermodynamically feasible). Then why if does not happen unless a flame is applied to start combustion, though `O_(2)` is available in abundance ?

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### Step-by-Step Solution: 1. **Understanding the Reaction**: The combustion of carbon in coal can produce carbon monoxide (CO) and carbon dioxide (CO₂). The Gibbs free energy change (ΔG) for these reactions is negative, indicating that they are thermodynamically feasible. This means that if the reaction were to occur, it would release energy. 2. **Thermodynamic vs. Kinetic Feasibility**: While the reaction is thermodynamically feasible (ΔG < 0), this does not mean that it will occur spontaneously at room temperature. The reaction also needs to overcome an energy barrier known as the activation energy. 3. **Activation Energy**: The activation energy is the minimum energy required to initiate a chemical reaction. In the case of the combustion of carbon, the energy required to break the bonds in the reactants (carbon and oxygen) and form new bonds in the products (CO or CO₂) is significant. ...
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