Page 7 - Pharmaceutical analytical chemistry |

does not take part in the reaction. In the above example, Na+ and OH-
ions appear on both sides of the equation. This means that nothing
happens to these ions as the reaction occurs, so they are cancelled and the
resulting equation is :

Ca2+ (aq) + CO32- (aq) ⎯→ CaCO3 (s)

Types of chemical reactions

1- Acid-base reactions ⎯→ involve the transfer of a H+ between
reactants.

2- Precipitation reactions ⎯→ you mix solutions of 2 ionic substances to
form a solid ionic substance (a ppt).

3- Oxidation-reduction reactions ⎯→ involve the transfer of electrons
between reactants.

4- Complex formation reactions⎯→ electron deficient metal ion forms a
complex with other ions of opposite charge or another molecule

A- Acid-base reactions

Acids have a sour taste while bases have a bitter taste and a soapy

feel. They cause color changes in certain dyes called acid-base

indicators which are dyes used to distinguish between acidic and

basic solutions, e.g.

indicator acid base

litmus red blue

phenolphthalein colorless pink

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