Excessive burning of fossil fuels like coal, natural gas and oil has led to the increase of CO₂ level.
Definition of Fossil fuels
Fossil fuel is defined as a generic term for non-renewable energy sources such as coal, coal products, natural gas, derived gas, crude oil, petroleum products and non-renewable wastes. Fossil fuel are hydrocarbons which are formed from the dead remains of plants and animals that are buried under soil and are burned as fuel.
When fossil fuels are burned they give out harmful gases such as carbon dioxide due to its organic content which led to increase in the CO₂ level over the past years.
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