Energy & Green Tech

Electric cars better for climate in 95% of the world

Fears that electric cars could actually increase carbon emissions are unfounded in almost all parts of the world, news research shows. Media reports have regularly questioned whether electric cars are really "greener" once ...

Energy & Green Tech

World fritters away half trillion dollars on coal support

Nations around the world risk wasting $640 billion by continuing to prop up the coal industry rather than investing in less expensive and environmentally friendlier wind and solar power initiatives.

Energy & Green Tech

How heat can be used to store renewable energy

The effect that fossil fuels are having on the climate emergency is driving an international push to use low-carbon sources of energy. At the moment, the best options for producing low-carbon energy on a large scale are wind ...

Energy & Green Tech

EU wants battery autonomy, but first it needs graphite

As Europe looks to declare its tech independence by becoming a leader in next-generation batteries, it will have to start by making its own graphite. The problem is, nearly all of it now comes from Asia, mainly China.

Energy & Green Tech

France shuts oldest reactors, but nuclear power still reigns

France will start closing its oldest atomic power plant on Saturday after 43 years in operation, the first in a series of reactor shutdowns but hardly a signal the country will reduce its reliance on nuclear energy anytime ...

Machine learning & AI

Artificial intelligence is becoming sustainable

A research group from Politecnico di Milano has developed a new computing circuit that can execute advanced operations, typical of neural networks for artificial intelligence, in one single operation.

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Carbon

Carbon (pronounced /ˈkɑrbən/) is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds. There are three naturally occurring isotopes, with 12C and 13C being stable, while 14C is radioactive, decaying with a half-life of about 5730 years. Carbon is one of the few elements known since antiquity. The name "carbon" comes from Latin language carbo, coal, and, in some Romance and Slavic languages, the word carbon can refer both to the element and to coal.

There are several allotropes of carbon of which the best known are graphite, diamond, and amorphous carbon. The physical properties of carbon vary widely with the allotropic form. For example, diamond is highly transparent, while graphite is opaque and black. Diamond is among the hardest materials known, while graphite is soft enough to form a streak on paper (hence its name, from the Greek word "to write"). Diamond has a very low electrical conductivity, while graphite is a very good conductor. Under normal conditions, diamond has the highest thermal conductivity of all known materials. All the allotropic forms are solids under normal conditions but graphite is the most thermodynamically stable.

All forms of carbon are highly stable, requiring high temperature to react even with oxygen. The most common oxidation state of carbon in inorganic compounds is +4, while +2 is found in carbon monoxide and other transition metal carbonyl complexes. The largest sources of inorganic carbon are limestones, dolomites and carbon dioxide, but significant quantities occur in organic deposits of coal, peat, oil and methane clathrates. Carbon forms more compounds than any other element, with almost ten million pure organic compounds described to date, which in turn are a tiny fraction of such compounds that are theoretically possible under standard conditions.

Carbon is one of the least abundant elements in the Earth's crust, but the fourth most abundant element in the universe by mass after hydrogen, helium, and oxygen. It is present in all known lifeforms, and in the human body carbon is the second most abundant element by mass (about 18.5%) after oxygen. This abundance, together with the unique diversity of organic compounds and their unusual polymer-forming ability at the temperatures commonly encountered on Earth, make this element the chemical basis of all known life.

This text uses material from Wikipedia, licensed under CC BY-SA