Page 7 - Analytical Chemistry 1
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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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