List at least four places/sources in which carbon is found.
1. Carbon is found in the atmosphere in the form of carbon dioxide (CO2) which is emitted by various natural processes such as respiration, volcanic eruptions, and forest fires, as well as human activities including burning of fossil fuels and deforestation.
2. Carbon is present in living organisms in various forms, as it is the key element in all organic compounds. It is found in plants in the form of carbohydrates, proteins, nucleic acids, and lipids. It exists in animals as well, in the same organic compounds that make up their cells and tissues.
3. Carbon is also found in fossil fuels such as coal, oil, and natural gas. These fuels were formed from the remains of ancient plants and organisms that were buried and subjected to high pressure and heat over millions of years.
4. Carbon is present in the Earth's crust in the form of minerals such as limestone (calcium carbonate), dolomite (magnesium calcium carbonate), and graphite. These minerals are formed through geological processes and contribute to the carbon cycle.