what is the definition of FLAME in chemistry?
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<flame test, test used in the identification of certain metals. It is based on the observation that light emitted by any element gives a unique spectrum when passed through a spectroscope. When a salt of the metal is introduced into a Bunsen burner flame, the metallic ion produces characteristic color in the flame. Some metals and the colors they produce are: barium, yellow-green; calcium, red-orange; copper salts (except halides), emerald green; copper halides or other copper salts moistened with hydrochloric acid, blue-green; lithium, crimson; potassium, violet; sodium, yellow; and strontium, scarlet. The value of this simple flame test is limited by interferences (e.g., the barium flame masks calcium, lithium, or strontium) and by ambiguities (e.g., rubidium and cesium produce the same color as potassium). A colored glass is sometimes used to filter out light from one metal; for instance, blue cobalt glass filters out the yellow of sodium.\n\n<The flame test is a procedure used in chemistry to detect the presence of certain metals. It involves introducing a sample to a flame, and observing the color that results. The test is based on the fact that each element has its own characteristic emission spectrum. Samples are often held on the looped end of a clean, nonreactive wire (it's best with platinum or gold, although nichrome is used as a substitute) or on the tip of a wood stirring stick soaked in water. Sodium is a common component or contaminant in many compounds and its spectrum tends to dominate over others. The test flame is often viewed through cobalt blue glass to filter out the yellow of sodium and allow for easier viewing of other metals.\n\nThe main advantage of the flame test is that it is fast and easy to conduct, and does not require any special equipment. However, the range of detected elements is small, and the test relies on the subjective experience of the experimentalist than any objective measurements. The test has difficulty detecting small concentrations of some elements, while too strong a result may be produced for certain others, which tends to drown out weaker signals. Finally, the test only gives qualitative information, not quantitative data about the actual proportion of elements in the sample.
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Burning is rapid oxidation. What's left after something has burned, are the elements that wouldn't oxidize rapidly.
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Philosophy:\nWater is the elixir of life.\nWhile Fire is the begining (of pain & struggle).\n\nScience:\nFor Fire to happen u need Source, Fuel and Heat as described in a Fire triangle.\nWater removes the heat whereby the triangle is incomplete and Fire is extinguished.
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burning is atmospheric OXIDATION
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A rapid, persistent chemical change that releases heat and light and is accompanied by flame, especially the exothermic oxidation of a combustible substance.\nAn oxidising reaction takes place which gives off light and heat to form a flame. The burning process converts oxygen and other substances into a mixture of gases, water vapour and small solid particles which we call smoke. The gases are mostly carbon dioxide - C02 and carbon monoxide - CO.\nThe smoke particles, or soot, are mostly unburned carbon (C). If you hold a polished metal spoon above a candle flame it will become stained with soot. Smoke contains water vapour which is produced when the hydrogen from the candle wax combines with oxygen in the air.
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States are solid, liquid, gas and plasma...there is no fire state.  Fire is a chemical reaction that occurs when an object is going from one state to another.  A physical reaction is like the melting of ice...it goes from a solid state to a liquid state.  Fire actually changes the chemical makeup of a substance, therefore it is a chemical reaction.\n\nAnd it definitely does NOT have "plasma in it"!  Plasma is extremely rare on earth.
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A luminous flame is [by comparison] a bright, light emmiting, usually yellow, flame.  For example, if you light a match and watch it burn, this is a luminous flame.\n\nA non-luminous flame is a flame in which the fuel is undergoing complete, or near complete, combustion.  A non-luminous flame (as the name implies) is much darker than a luminous flame and does not emmit as much light.  The color is generally blue and the flame temperature is much higher than that of a num-luminous flame.\nOne can easily adjust a busen burner or propane torch to make a non-luminous flame.\n\nSo, in short, the differences are in:\n-color or the flame\n-temperature of the flame\n-percentage of fuel combusted
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Burning is a chemical change. Oxygen reacts with the material that you burn and converts it into the corresponding oxide. You start with one chemical and end up with another in the burning process. In the case of boiling, a liquid is converted into gaseous (vapour) state. Here the material is same; only its physical form is different before and after boiling. Hence it is a physical change.
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Fire, as a label, is a variable. \n"n.\n1.a. A rapid, persistent chemical change that releases heat and light and is accompanied by flame, especially the exothermic oxidation of a combustible substance." (1)\n\nTo strip out the longer words, fire is something combining with oxygen rapidly enough to produce heat and to be seen as a flame.\n\nDifferent materials do this at different temperatures. The temperature where a fire starts is called a flash point.\n\n"Flash point is the lowest temperature at which a liquid can form an ignitable\nmixture in ... The fire point is usually a few degrees above the flash point. ..." (2)\n\nHere are some sample *fire points* from Wikipedia:\n"   * Silane: <70°F (21°C)\n    * White phosphorus: 93°F (34°C)\n    * Carbon disulfide: 212°F (100°C)\n    * Gasoline: 495°F (257°C)\n    * Butane: 806°F (430°C)\n    * Magnesium: 883°F (473°C)\n    * Hydrogen: 1060°F (571°C)" (3)\n\nWhere we say "ouch" is our "pain point." (4)\n\nIt's a good idea to keep fingers out of fire, but burning ourselves does not need fire. Flame is not the only factor. I have been burnt by hot roofing tar -- 500 degrees F, but not on fire.\n\nThat's probably more than you wanted to know from this question, but it's been sitting here a couple of hours so I thought I'd essay it.
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Spontaneous combustion?
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Ok, what gas is required for combustion??  OXYGEN!\nHydrogen and oxygen combine and release large amounts of energy/heat while form water in small amounts (in the form of vapor).  \n\nAs for other gases, carbon is the element "burning", but there must be oxygen present in the moluecule or in the environment to burn.\n\nThis is different for hydrogen in stars, which are undergoing fusion.
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The process of combustion, or burning, is simply combining something with oxygen very rapidly, in a reaction that releases heat. When hydrogen burns, the result is water, which is just fully oxidized hydrogen. In effect, water is the "ash" of burned hydrogen. \n\nAnd like all other forms of ash, because water is already fully oxidized, it can no longer accept oxygen, and therefore cannot burn.
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Spontaneous human combustion (SHC) is the alleged process of a human body catching fire as a result of heat generated by internal chemical or nuclear action. While no one has ever witnessed SHC, several deaths involving fire have been attributed to SHC by investigators and storytellers
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The most common flames are glowing carbon (all your examples are carbon based fuels) and the gases in air, most notably oxygen. \n\nPretty much a 'normal' flame is yellowish (carbon glowing) and a bit of blue (oxygen glowing) on the bottom.\n\nThe oxygen supply determines the color changes more than anything. More oxygen would push the yellow toward white and the blue increases.\n\nGet an "A".
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no.  combustion is an exothermic reaction that relies on the oxidation of a fuel.  oxygen gas is an excellent oxidizer (so good in fact, that oxidation was named after it!) but without any fuel to oxidize, nothing will happen.
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Fire is not matter. The combustible material is a 'solid' like  wood, but can be a 'liquid' like gasoline. The wood combusts, releasing 'gases' such as Carbon Monoxide and solids such as ash particulates. The "fire" is the energy released in the form of heat and light. That's my simple explanation.
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In chemical qualitive analysis, this is known as a flame test.  Many metals (and some non-metals) have distinctive colors.\n\nThe heat of the flame excites one or more electrons of the metal atom causing it to go to a higher energy state.  When the electron returns to the "ground state" electromagnetic energy is released and this appears as light of a specific color.