exactly three grams of hydrogen, eight grams of oxygen reacted to.
exactly one gram of hydrogen, etc.).
Amedeo Avogadro also added to the understanding of chemical .
reactions. He said that all gasses at the same pressure, volume.
and temperature contain the same number of particles. This idea.
took a long time to be accepted. His ideas lead to the.
subscripts used in the formulas for gasses.
From the work of these and many other chemists, we now have.
a mostly complete knowledge of chemical reactions. 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.