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What is an example of an ionic bond?

An ionic bond forms when two oppositely charged ions (one negative and one positive), such as those of a metal and a non-metal, become attracted to one another and end up causing a transfer of electrons. The electrons are usually transferred from metals to non-metals, making the metal that lost the electrons positively charged and the non-metal that gained them negatively charged. Another name for positively-charged ions is "cations," and another name for negatively-charged ions is "anions."

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How many electrons does tin have?

According to About.com, tin is classified as a metal and is soft and malleable, with a silvery-white appearance. It is used in the manufacturing of cans, as well as in many products to prevent corrosion. Most tin comes from cassiterite, which, according to Reference.com, is a dark mineral also known as tin dioxide. This mineral is found in igneous rocks.

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What are some examples of inorganic compounds?

Organic compounds have molecules that are based in carbon and hydrogen. Proteins, lipids, nucleic acids and carbohydrates are all examples of organic compounds.These differ greatly from inorganic compounds.Organic compounds have carbon because carbon has the ability to form chemical bonds on an atom. However, there are a few inorganic compounds that contain carbon like carbon dioxide and carbon monoxide. This has raised the question among scientists about the way these compounds have been classified. Some argue that the classification of inorganic and organic compounds should be restructured a..

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What is the difference between natural and human-made disasters?

All disasters are put into two main categories: natural and human-made. According to RestoreYourEconomy.org, natural disasters include droughts, earthquakes, floods, tornadoes, wildfire, sinkholes, blizzards, hail, agricultural pests, diseases and hurricanes. Human-made disasters include power blackouts, hazardous material spills, explosions, chemical or biological attacks, nuclear blasts and radiological emergencies.\nThe main difference is what creates the disaster. Humans are the only beings that can create nuclear power, so a nuclear blast is a human-made disaster. On the other hand, human..

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What is the difference between primary and secondary succession?

In primary succession, bare rock or sand is the substrate upon which the pioneer species act. Primary succession occurs in places that are the result of lava flows or where glaciers have retreated. Soil is not yet present, so no plants or animals can survive in such a region.\nPioneer species are the lichens and moss. These organisms break down rock, turning it into soil for plants to put down roots. Shrubs and grasses then start taking advantage of the nutritive soil. Small trees come into the area, replacing the smaller plants. Leaves that fall from these shrubs and small trees produce leaf ..

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What is the wavelength of the photon emitted when a hydrogen atom goes from the second energy level to the first energy level?

Electrons residing at the first energy level have -13.6 electron volts of energy, and those residing at the second energy level have -3.4 electron volts of energy. The energy difference from level one to level two is equal to the amount of energy required for an electron to jump between the levels. A photon emits light at a wavelength directly corresponding to its energy value. The wavelength in meters is determined by multiplying the speed of light and Planck's constant, then dividing by the photon's energy in electron volts.\nInterestingly, for an electron to jump back up, from lev..

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What types of wildlife have gone extinct in Africa?

The Madeiran Large White butterfly went extinct due to deforestation and pollution from agricultural products. The West African black rhino was officially declared extinct in 2006 due to poaching and human infringement in its living spaces. The rhinoceros' horn is a prized possession in many parts of the world. The Quagga was a relative of zebras but was wiped out because of its hide. Bubal antelopes were native to North Africa but were hunted by humans and driven to extinction.

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What does the color silver symbolize?

The meaning of the color silver can also denote affluence and honor because its metal counterpart is minted as money and worn as jewelry. People who wear silver are believed to be modern and elegant. In the past, silver was worn by royalty and other dignified members of a society, and silver remains a customary gift to give a respected couple on their 25th wedding anniversary. The term "silver tongued" came from the belief that a person could gain public speaking ability by wearing the color silver.\nWhether in its natural metal form or a sparkly shade, silver will continue to have strong sign..

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What sounds can only kids hear?

As BBC News explains, this phenomenon is something that security contractors have tried to take advantage of in a practical sense. The "Mosquito" is a device designed to deter youth crime in subways and other public areas. Initially released in 2005, the Mosquito anti-loitering device emits a loud, high pitched audio pulse, only audible to those under the age of 25.

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What are some exercises for Lumbar Spondylosis?

Lumbar spondylosis is the age-related deterioration of the spinal column in the lumbar region. It is not a disease itself but a descriptive medical term because its causes include a number of different disease processes, including osteoarthritis and degenerative disc disease, as the Laser Spine Institute explains. Depending on the type, location and stage of spinal degeneration, lumbar spondylosis is first managed conservatively using some combination of anti-inflammatory and pain medicines in conjunction with strength training and stretching.\nStretching elongates the spine during the exercis..

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