Chemical Reactions Essay

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Chemical Reactions

Chemical reactions are the heart of chemistry. People have always known that they exist.
The Ancient Greeks were the firsts to speculate on the composition of matter. They thought that it was possible that individual particles made up matter.

Later, in the Seventeenth Century, a German chemist named Georg Ernst Stahl was the first to postulate on chemical reaction, specifically, combustion. He said that a substance called phlogiston escaped into the air from all substances during combustion.
He explained that a burning candle would go out if a candle snuffer was put over it because the air inside the snuffer became saturated with phlogiston. According to his ideas, wood is made up of phlogiston and ash,
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There are now many classification systems to classify the different types of reactions. These include decomposition, polymerization, chain reactions, substitute reactions, elimination reactions, addition reactions, ionic reactions, and oxidation-reduction reactions.

Decomposition reactions are reactions in which a substance breaks into smaller parts. As an example, ammonium carbonate will decompose into ammonia, carbon dioxide, and water. Polymerization reactions are reactions in which simpler substances combine to form a complex substance. The thing that makes this reaction unusual is that the final product is composed of hundreds of the simpler reagent (a substance that contributes to a chemical reaction) species. One example is the polymerization of terephthalic acid with ethylene glycol to form the polymer called Dacron, a fibre, or Mylar, in sheet form:

nH2OC(C6H4)CO2H + nHOCH2CH2OH -> [...OC(C6H4)CO2CH2CH2O...]n 2nH2O

in which n is a large number of moles. A chain reaction is a series of smaller reactions in which the previous reaction forms a reagent for the next reaction. The synthesis of hydrogen bromide is a good example:

H2 + Br2 -> 2HBr

This is a simple equation that doesn’t properly prove the reaction. It is very complex and starts with this:

Br2 -> 2Br

The next three reactions are related and should be grouped together. A substation reaction is a reaction in which a substance loses one or more atoms and
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