What Is Elemental Carbon?

The "protagonist" of the organic world--carbon C Although not too small on the earth, carbon is not too much. Calculated by weight, it accounts for four thousandths of the total weight of each element in the crust. One-fifteenth, but the carbon footprint is global.

Elemental carbon

"Protagonist" of the organic world-carbon C

Although not too small, but not too much carbon on earth, it accounts for four thousandths of the total weight of each element in the earth's crust by weight, and does not exceed one and one-half thousandth of the total atomic weight. Has a global footprint.

In nature, there is pure carbon. For example,

Diamond and graphite are both carbon. Why are they so different? This is because they have different crystal structures. In diamond, the arrangement of carbon atoms is very regular. There are four equidistant carbon atoms around each carbon atom, forming a regular tetrahedron (Figure 14), so diamond has a large specific gravity and is hard. The crystal structure of graphite is layered (Figure 15). The distance between the layers is large and it is easy to slide, so the specific gravity of graphite is smaller than that of diamond, and it is soft and slippery. Diamond and graphite are called "allotropes". There are two kinds of objects with different properties composed of the same element.

Charcoal, coal, and ashes are also carbon (containing some impurities) and are called amorphous carbon. China is the first country in the world to use coal as fuel. As early as more than 3,000 years ago, China has used "black stone" (ie, coal) for heating and cooking. Coal is known as "the grain of industry". Just as the people of our country celebrated the victory of the 10th National Congress of the Communist Party with more outstanding achievements, a large modern open-pit coal mine was newly built in China and has been put into production. Coal is the most important industrial fuel. After coking, more than 500 industrial raw materials such as benzene and phenol can be obtained from coal tar. The soot in the chimney is also pure carbon. Soot is used to make ink, ink, and ink. Adding soot to rubber can increase its mechanical strength ten times. 90% of soot is used as a "reinforcing agent" for rubber.

After burning wood, coal, charcoal, etc., carbon dioxide is generated. Carbon dioxide is a colorless and odorless gas, slightly heavier than air, and the content in air is three ten thousandths. Under pressure, carbon dioxide can easily turn into a colorless liquid. At lower temperatures, it turns into white, snowflake-like crystals-dry ice. Carbon dioxide is easily soluble in water, and carbon dioxide is dissolved in the soda. Carbon dioxide does not support combustion, and the gas emitted by chemical fire extinguishing agents is carbon dioxide. Humans, animals, and plants constantly emit carbon dioxide during breathing. According to statistics, humans exhale more than 1.8 billion tons of carbon dioxide every year. And the chimneys of factories, trains, and ships around the world emit more than 10 billion tons of carbon dioxide every year. If this continues, will the world become a world of carbon dioxide? No, no, it turns out that there is a wonderful cycle in nature: during photosynthesis, plants absorb a large amount of carbon dioxide and spit out oxygen, so that carbon dioxide will not increase.

Incomplete combustion of coal produces carbon monoxide. Carbon monoxide is a highly toxic gas, and "gas" is poisoned. This "gas" is carbon monoxide. Carbon monoxide is an important fuel and raw material in industry. When carbon monoxide is burned, a blue flame is generated. Light blue flames are often seen on the coal seam of the furnace. That is, carbon monoxide is burning.

On the mountain, the huge limestone is also a carbon compound-calcium carbonate. Limestone can be used as building materials, paving, and bridge building. Limestone can be turned into quicklime (calcium oxide) when burned in a lime kiln. Quicklime is often used as a building binder or to paint walls. When quicklime meets water, it becomes mature lime (calcium hydroxide) and releases a lot of heat, so that eggs can be cooked.

Petroleum is the "depot" of carbon compounds. Petroleum is mainly a mixture of hydrocarbons with different boiling points. Petroleum is known as the "blood of industry". It can extract gasoline, kerosene, and diesel from petroleum. It is the most important liquid fuel in the industry and is used to start various internal combustion engines. Using petroleum as raw material, three major synthetic materials such as plastic, synthetic fiber, and synthetic rubber can also be manufactured.

Natural gas often lives with oil mines. The main component of natural gas is methane CH4, which is also a hydrocarbon and is used as a gas fuel and chemical raw material.

Carbon is the foundation of life. All organic matter in plants and animals is a carbon compoundproteins, oils, starches, sugars, chlorophyll, heme, hormones, and carbon. In industry, carbon compounds are also very important. Most of the organic chemical industries, such as plastics, chemical fibers, rubber, perfumes, dyes, and pharmaceuticals, produce carbon compounds.

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