Question

Fuels like coal, petrol, diesel and natural gas are burnt ______ gas is released in large volumes.

Answer 1

Burning of fossil fuels:-

• We know that, when a substance reacts with oxygen, it gives off heat and emits light, this is called combustion.
• Now fossil fuels like coal, natural gas, petroleum, and petrol, are nothing but materials that contain hydrocarbons in them.
• These fuels when burnt, liberate carbon dioxide$\left({\mathrm{CO}}_2\right)$ gas in a large amount.
• This carbon dioxide emitted is harmful to us.
• Due to the release of this carbon dioxide gas, the temperature of our atmosphere slowly increases, and this leads to global warming.
• It also affects the health of human beings as well as animals, and thus this rising level of carbon dioxide changes the climate.
• The common reaction for the combustion of carbon is:$\underset{\mathrm{Carbon}}{\mathrm{C}\left(\mathrm{s}\right)}+\underset{\mathrm{Oxygen}}{{\mathrm{O}}_2\left(\mathrm{g}\right)}\to \underset{\mathrm{Carbon}\mathrm{dioxide}\mathrm{gas}}{{\mathrm{CO}}_2\left(\mathrm{g}\right)(\uparrow )}+\mathrm{heat}+\mathrm{light}$
• The generalised reaction for the combustion of alkanes are:

$\underset{\mathrm{Alkane}}{{\mathrm{C}}_{\mathrm{n}}{\mathrm{H}}_{2\mathrm{n}+2}}+\underset{\mathrm{Oxygen}}{\left(\frac{(3\mathrm{n}+1)}{2}\right){\mathrm{O}}_2}\to \underset{\mathrm{Crabon}\mathrm{dioxide}}{{\mathrm{nCO}}_2\left(\mathrm{g}\right)}+\underset{\mathrm{Water}}{(\mathrm{n}+1){\mathrm{H}}_2\mathrm{O}\left(\mathrm{g}\right)}$

Therefore, fuels like coal, petrol, diesel, and natural gas are burnt, carbon dioxide gas is released in large volumes.