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Why does burning coal release carbon dioxide?

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coal utilization Cross-regenerative coke oven. (A) Cross section, showing the alternating arrangement of flue walls and ovens; (B) longitudinal section, showing (left) a series of combustion flues in a single flue wall and (right) part of a long, slotlike oven.

Burning coal releases carbon dioxide because coal is a carbon-rich material formed from ancient plant remains. During the process of combustion, the carbon contained within the coal reacts with oxygen in an oxidation reaction.12

This chemical reaction can be represented as:
carbon + oxygen = carbon dioxide2

Because this reaction is exothermic, it releases significant amounts of heat, which is why coal is utilized as a primary fossil fuel for energy production. However, this process also emits large quantities of carbon dioxide into the atmosphere, making coal the single largest contributor to anthropogenic climate change and a major driver of global warming. Given the severe environmental impact of these emissions, there is a strong ethical imperative to transition toward renewable energies to protect the planet's climate and future habitability.123