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Carbon (from Latin carbo 'coal') is a chemical element; it has symbol C and atomic number 6. It is nonmetallic and tetravalent—meaning that its atoms are able to form up to four covalent bonds due to its valence shell exhibiting 4 electrons. It belongs to group 14 of the periodic table. [16] Carbon makes up about 0.025 percent of Earth's ...
The carbon cycle is that part of the biogeochemical cycle by which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and atmosphere of Earth. Other major biogeochemical cycles include the nitrogen cycle and the water cycle. Carbon is the main component of biological compounds as well as a major component of many ...
Carbon dioxide is a chemical compound with the chemical formula CO 2.It is made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature, and as the source of available carbon in the carbon cycle, atmospheric CO 2 is the primary carbon source for life on Earth.
Carbon group. The carbon group is a periodic table group consisting of carbon (C), silicon (Si), germanium (Ge), tin (Sn), lead (Pb), and flerovium (Fl). It lies within the p-block . In modern IUPAC notation, it is called group 14. In the field of semiconductor physics, it is still universally called group IV.
Climate change. Changes in surface air temperature over the past 50 years. [ 1] The Arctic has warmed the most, and temperatures on land have generally increased more than sea surface temperatures. Earth's average surface air temperature has increased almost 1.5 °C (about 2.5 °F) since the Industrial Revolution.
A carbon footprint (or greenhouse gas footprint) is a calculated value or index that makes it possible to compare the total amount of greenhouse gases that an activity, product, company or country adds to the atmosphere. Carbon footprints are usually reported in tonnes of emissions ( CO 2 -equivalent) per unit of comparison.
Carbon dioxide (CO 2) is the main greenhouse gas resulting from human activities. It accounts for more than half of warming. Methane (CH 4) emissions have almost the same short-term impact. [ 5] Nitrous oxide (N 2 O) and fluorinated gases (F-gases) play a lesser role in comparison.
In a 2018 study, carbon was found to compose approximately 550 billion tons of all life on Earth. [ 16][ 17] It is the second most abundant element in the human body by mass (about 18.5%) after oxygen. [ 18] The most important characteristics of carbon as a basis for the chemistry of cellular life are that each carbon atom is capable of forming ...