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What are the characteristics of a molecular compound?

The bonds formed by the sharing of electrons are called covalent bonds. Molecular compounds can have single, double or a triple covalent bond depending on the number of pairs of electrons shared between atoms forming the bond.\nThe covalent bonds between atoms in a molecular compound are strong, and this gives rise to specific shapes of molecules in covalent compounds. A molecule of hydrogen is formed when two hydrogen atoms share one pair of electrons to complete the doublet of electrons in the outermost shell.\nA molecule of oxygen is formed when two atoms of oxygen share a pair of electrons..

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What are non-conductors of electricity?

Materials can either be insulators or conductors. Conductors have a low amount of resistivity, which means electrons can flow through them without much impedance. Most conductors are metals, although there are exceptions.Having a small amount of valence electrons means that metal atoms are always trying to give away electrons. This property allows electrons to move from atom to atom very efficiently. In insulators, atoms do not want to give away electrons, which halts electron flow.

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What type of rock is mica?

When mica is classified, it is considered to have an almost perfect cleavage when it breaks. This can also be called a slaty cleavage, but either term basically means that the rock splits at parallel or planar surfaces and the minerals are so small that they cannot be seen by the naked eye. This gives them a smoother look when they break and makes it seem more like they have been cut.

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What does a troy ounce of gold mean?

A medieval practice of weighting, the troy ounce weights system originated in Troyes, France. The unit of measurement was one of the first imperial units — a measurement adopted by the British Empire\nto create a unified weighting system. The troy ounce outweighs a regular, or avoirdupois, ounce by roughly 2.75 grams. To convert avoirdupois ounces to troy ounces, multiply the number of regular ounces by 0.911458333333. When the price of gold is reported, it is given in troy ounces.

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What is the history and purpose of cryonics?

Cryonics began in 1964 with a book titled "The Prospect of Immortality" by physics teacher Robert Ettinger. Ettinger proposed that a person could be frozen and revived once the technology to safely thaw a human body had been developed. In 1967, psychologist Dr. James Bedford became the first person to be cryogenically frozen. By early 2004, the Alcor Life Extension Foundation, one of the world's largest cryonics companies, had 59 patients in cryosuspension.\nCryonic freezing begins once the patient is legally dead. Technicians replace the body's water with a chemical mixture called a..

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Where is the cell membrane located?

The cell membrane protects the integrity of the remainder of the cell by selectively allowing substances to pass in and out of the structure. Its primary components are lipids and proteins. Phospholipids automatically arrange themselves to shield the cell from its surrounding polar liquids. Proteins in the cell wall form gates that allow the cell to absorb fluids and other molecules as needed.\nCholesterol is one of the lipids found in the cell walls of animals but not in plants. Depending on the location of the cell in the body, the membrane contains from 20 to 80 percent cholesterol. While s..

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What is the difference between lux and lumens?

Lux is more accurately described as the amount of luminous flux spread over a certain area. For example, if spread over about 1000 square meters, 1000 lumens hit each square meter with about 1 lux. If that same 1000 lumens is focused to one square meter, its intensity is equal to 1000 lux. In scientific equations and calculations, lux is represented by the lx symbol.\nMeasuring lumens is accomplished by measuring the amount of light visible to the human eye from a source, such as a lightbulb or the sun. Artificial forms of light, such as lamps or lightbulbs, are labelled by lumens and can have..

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What is the slowest fish?

Two species of the pygmy seahorse, the Bargibant and the Denise, typically thrive in gorgonian coral in parts of Southeast Asia. However, they can also be found in other locations, such as Queensland, Australia's Great Barrier Reef. These fish use natural camouflage to protect themselves from predators, and they also avoid living in large groups. Unlike other kinds of seahorses, pygmy seahorses use pouches within their bodies to protect their young.

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What is the difference between ionic and molecular compounds?

When one pair of electrons is shared, it forms a single covalent bond. Similarly, a double and triple covalent bond is formed by the sharing of two and three pairs of electrons. Ionic compounds are formed between metals as well as non-metals while molecular compounds are formed only between non-metals. Examples of ionic compounds are common salt and sugar. Examples of molecular compounds are hydrogen molecule, nitrogen molecule and water.\nIonic compounds are crystalline with ions f,orming a three-dimensional lattice network. Solid molecular compounds are amorphous and have a powdery texture. ..

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When will Halley's Comet be returning?

The comet, named after the English astronomer Edmond Halley, is one of the most famous comets in the world. Since it passes by Earth every 76 years, it is possible for a person to see it twice in his or her lifetime.\n\nIn order to view the comet, a good pair of binoculars is needed. Scientists also recommend getting as far away from light pollution (city lights) to see the comet along the horizon.

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