BIG ENCYCLOPEDIA FOR CHILDREN AND ADULTS
What is talc? Detailed answer Directory / Big encyclopedia. Questions for quiz and self-education Did you know? What is the latitude and longitude? Talc is the softest mineral known to man. It is so soft that it can be easily scraped off from the whole piece with the help of nails. It is a small flake or flake of a mineral that has a silvery-white or pale green color. In solid form, talc is known as soapstone. In this case, it is a grayish or greenish mineral, often covered with brown spots, very soft and greasy to the touch. The best talc is mined in Piedmont in Italy. However, its deposits are found in many countries, including England, Canada, Germany, Russia and Zimbabwe. The world's largest reserves of it are located on the Atlantic coast of the United States. Due to the heat-insulating properties of soapstone, in the old days it was often used to make kitchen utensils, for which it received the name "pot stone". It has also been used as a material for pipes and sinks. Since soapstone is poorly soluble in acids, the walls and bottoms of laboratory vessels used to store caustic liquids are covered with plates of it. It is a poor conductor of electricity and therefore finds use as an insulating material for switchboards and other similar objects. For lining various surfaces, it uses its property to become harder when heated. The ancient Egyptians carved magical talismans and amulets from talc and covered them with colored azure. Approximately three-quarters of the world's talc is used to make cosmetics, glazed tiles and other ceramics, paper, rubber and roofing materials. Author: Likum A. Random interesting fact from the Great Encyclopedia: What did Galileo Galilei see through the telescope? In 1609, Galileo learned that a far-seeing device had appeared in Holland (this is how the word "telescope" is translated from Greek). The basis of this device is a combination of optical glasses. He collected several telescopes, each subsequent one gave an increasing increase, and if the first magnified only 3,5 times, then the best of the Galilean telescopes gave an increase of 33 times. Galileo made great discoveries with these homemade instruments. The moon is not an ethereal luminary of light gases, but a planet similar to the Earth, with vast plains and mountains, the height of which Galileo determined by the length of the shadow they cast.
Observing the Sun (Galileo put smoked glass to the lens), the scientist discovered spots that move. Giordano Bruno's guess was confirmed: the Sun rotates around its axis, just like the Earth. Through a telescope, Jupiter is seen not alone, but with four satellites that revolve around it, as if it were a miniature solar system. The Milky Way, a nebulous streak that crosses the sky, is seen through a telescope as crumbling into countless stars.Test your knowledge! Did you know... ▪ Which subway is the longest? ▪ Who painted the nude version of the Mona Lisa? See other articles Section Big encyclopedia. Questions for quiz and self-education. Read and write useful comments on this article. Latest news of science and technology, new electronics: Machine for thinning flowers in gardens
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