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Chemical reactions happen in laboratories and in nature.

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During a chemical reaction, the atoms within substances are rearranged and joined together in different ways.

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The substances that start a reaction are called reactants, and what they produce is called the product.

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the new substance can only be separated by another chemical reaction so simple separation

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methods like filtration evaporation and distillation won't work several things

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indicate that a chemical reaction might have taken place energy change

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color change the production of gas and the formation of a precipitate a solid produced

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when two solutions are combined the chemical reaction called combustion produces heat and

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light and new substances like smoke and ash for burning to take place there must be oxygen fuel

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such as wood and heat oxidation occurs when oxygen is added to a substance some metals

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like iron become rusty and food begins to discolor and break down fermentation takes

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place without oxygen. It involves breaking down a substance by adding microorganisms to it.

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This is how dough rises. Fermentation is also used to make yogurt from milk.

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The next time you sit in front of a fire or see an old rusty car,

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think of the chemical reactions involved and how everything in life is constantly changing.