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Why does fire burn?

After a fuel is heated to its burning point, part of it is decomposed and released as a volatile gas. This gas is known as smoke and contains hydrogen, carbon and oxygen. The remainder forms char, which is mostly carbon and ash and includes any other noncombustible elements. The next part of the burning process requires the volatile gases released to reach a certain temperature, which is about 500 degrees Fahrenheit for wood. Once this temperature has been reached, the molecules in the gas break down and the atoms combine with oxygen to form carbon dioxide, water, carbon monoxide, nitrogen and..

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Where are geysers located?

Magma chambers are closer to the Earth's surface when they are near tectonic plate boundaries. Energy is created as the boundaries collide. The heat produced by both magma chambers and boundary collisions raises the temperature of water that filters down through the ground from rain and snow. As the water heats, it begins to rise back to the surface through vents and crevices in the rock. When the water passes through the openings, it becomes constricted, resulting in a release of pressure as a geyser when it reaches the surface. Hot springs occur when heated water returns to the surface ..

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How many atoms are in Ca(NO3)2?

In appearance, this compound is white and granular. Calcium nitrate is soluble in water and has a density of 2.5 grams per cubic centimeters. Its melting point is 1,040 degrees Fahrenheit.The main applications of calcium nitrate are in fertilizers, explosive devices and fireworks. If this substance burns in a fire, it can give off toxic fumes. If inhaled, this substance can cause coughing and also irritate the mucous membranes.

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What is the melting point of citric acid?

Citric acid is a white crystalline powder at room temperature. It occurs in nature in most citrus fruits such as lemon, oranges and peaches. It is soluble in water and in organic compounds such as alcohols and ethers.\nCitric acid is an organic compound with a sour taste. It is often used as a preservative. It is added to food preparations to provide a lemony flavor. Citric acid is used as a cleaning agent. It is often used to soften hard water containing salts of calcium and magnesium.

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What is the function of the liver?

After food is broken down in the digestive system, nutrients travel by blood through the liver where it is either turned into stored energy for quick use or made into chemicals the body needs. Bile is made by the liver and stored in the gallbladder. It helps digest particularly fatty food. The liver also removes old cells, drugs and hormones from the bloodstream. Among the proteins the liver produces, it manufactures several responsible for blood clotting.

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What are some common questions in a biology quiz?

Basic functions of the human body, abnormalities and physiological responses are common categories on biology quizzes. Questions in these areas commonly ask about diseases and immune responses, including contracted diseases, genetic disorders, cell destruction and regeneration. Autoimmune disorders and microbial metabolism are also common human body topics on biology quizzes.\nIn addition to biology of the body, questions on biology quizzes also include those relating to household air and the surface dangers of bacteria, mold, mildew and viruses; the environmental biology of soils, waste water..

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What is 5 ounces in milliliters?

Since rounding errors can occur, it's always important to check your math when calculating ounce to milliliter conversions. A milliliter is the equivalent of 1 cubic centimeter, and is a non-SI unit that is accepted for use by the International System of Units (SI).The SI-derived unit is the cubic meter for volume. Ounces are used in both the United States and the United Kingdom, though the actual measurements are slightly different. Five U.K. ounces equals 142.07 milliliters after rounding.

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How many people were left homeless after Hurricane Katrina?

Although Katrina affected over 90,000 square miles of the Gulf Coast, New Orleans residents were the most heavily affected by the storm, as the city's system of levees was poorly equipped to handle the stresses of a powerful hurricane. Moreover, the city's average elevation is 6 feet below sea level, forming a basin into which nearby bodies of water drained when engorged by the torrential downpours.

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What are materials that are usually good conductors of electricity?

An electric current is the flow of an electric charge as an electron passes from atom to atom. In order to pass electrons, a substance must have space for electrons to move in while holding electrons loosely enough that they pass on easily. Metals have outer valence-shell electrons that wander, moving freely from atom to atom. When a new electron is introduced, it causes a chain reaction, much like a row of falling dominoes, that pushes electrons on down the line, carrying the current. Dissolved substances with an ionic bond, for instance table salt dissolved in water, carry charges similarly,..

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How are hibernation and estivation different?

Both hibernation and estivation lower an animal's body temperature and metabolic rate. This reduced rate of metabolism allows the animal to survive for long periods without food. Many bird species undergo a similar process called torpor.\nHibernation is always a reaction to reduced food supply, but estivation may occur in response to either lowered availability of food or conditions too hot and dry for the animal to survive. Animals burrow to cooler underground locations prior to estivation to escape these conditions. Hibernation is associated with cold temperatures because food is scarce..

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