1. Acids and Bases

2. Indicators Substances that change colour in acids or bases
can be used to tell if a substance is acidic, basic or neutral
many are form natural sources (red cabbage, lichen (litmus paper), tea leaves, beets)
synthetic ones
turn different
colours for
different pH
levels

3. pH means power of the [H]+ ion
refers to the concentration of Hydrogen ions in a solution
indicates the strength of acids and bases on a scale of 0 -14
pH of 7 is neutral (neither acid or base)
each number represents a strength 10X more powerful (e.g. pH 10 is 10X more basic than pH 9, and pH 2 is 1000X more acidic than pH 5)

4. pH of Everyday

5. Properties of Acids Dissolve in water to form [H]+ ions
Turn litmus paper red
React with metals to form H2 gas
Taste sour
Feels like water but can burn your skin

6. Properties of Bases Dissolve in water to produce [OH]- ions
turns litmus blue
tastes bitter
feels slippery to the touch (detergents)

7. Neutralization Reactions
When a base and an acid react together to form a salt and water
HCl + NaOH NaCl + H2O
Acid Base = Salt Water
(this example is table salt, but a "salt" is any compound made up of positive and negative ion pairs)
The products of the reaction are neither acid or base - they are neutral
Prediction activity…

8. Practice Try these Neutralization reactions + balance!!: H2SO + NaOH
HCl + Ca(OH)2
HCl + Li(OH)
H2CO3 + KOH