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Stages and techniques


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Chemical synthesis is the procedure used to make useful compounds. This often involves a number of chemical reactions and other processes.

Stages in chemical synthesis

In the synthesis of any chemical compound in useful quantities, there are a number of common stages:

  1. Choosing a reaction to make the desired product

    Reactants must be readily available and as cheap as possible. The reaction must also be as easy to carry out as possible.

  2. Carrying out a risk assessment

    All procedures carry a risk. The risk involved must be as small as possible.

  3. Working out the quantities of reactants to use

    Using too much of one of the reactants would be wasteful, and could contaminate the product.

  4. Carrying out the reaction using suitable apparatus, in the right conditions

    The reaction must take place as quickly as possible, while still being under control. This will make the product as cheaply as possible. The correct concentrations, pressure or catalyst may be required.

  5. Separating the product from the reaction mixture

    Some of the reactants may remain, and by-products may be produced.

  6. Purifying the product

    Some products need to be of high purity. This is particularly true of pharmaceuticals.

  7. Measuring the yield and checking the purity of the product

    It is important to know how much product is made from how much reactant, and whether the product contains any other compounds.


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