2. Objective
s Describe the properties of acids.
s Explain the process of ionization.
s Identify common acids by formula.
3. Properties of Acids
s Acids taste sour!
s Acids conduct electricity! (electrolytes)
s Acids have specific reactions with chemicals
called indicators
– Common indicators
s Bromthymol Blue + Acid = Yellow
s Phenolphthalein + Acid = stays clear (no change)
s Litmus + Acid = Red
s Cabbage Juice + Acid = Red
4. Demo: Carbonating Water
s Respiration:
C6H12O6 + O2 --> H2O + CO2
s When you breathe out, CO2 is dissolved in
the water. When CO2 mixes with water it
becomes carbonic acid which changes the
color of the Bromthymol Blue to yellow!
Bromothymol Blue Indicator Reaction
5. Ionization of Acids
s Acids always have Hydrogen in the front of their formula
– The “H” separates when the acid is mixed with water,
becoming a “Hydrogen Ion” or “H+”
– The H+ attaches to water molecules making H3O+ or a
Hydronium Ion
s H+ + H O -> H O+
2 3
– The ions in solutions are why acids conduct electricity
– The stronger the acid- the more complete the
disassociation of H+ from the formula (see next)
6.
7. Common Acids
s Strong Acids
s HCl (Hydrochloric Acid) = found in your stomach!
s H SO (Sulfuric Acid) = Industrial uses, car batteries
2 4
s HNO3 (Nitric Acid) = Making TNT, making fertilizers.
s Weak Acids
s H2CO3 (Carbonic Acid) = Carbonating Beverages
s H3BO3 (Boric Acid) = Washing eyes
s HC2H3O2 (Acetic Acid) = Vinegar
s H3C6H5O7 (Citric Acid) = Making soft drinks, found in fruit