1. Neutralisation (Please copy these main points to your books)
                                                  
(Please copy these main points to your books)
(And ensure that you read page 59-60)

2. pH
The CONCENTRATION of hydrogen ions …wether an acid is weak or strong or if a substance is a base or not is measured on the pH scale
In an acid there are more hydrogen ions than Hydroxide
In a base there are more hydroxide than hydrogen ions
Pure water is neither- its neutral pH 7- has = numbers of both types of ions

3. Ph SCALE You have one to colour on page 6 of your booklet
USE PAGE 59 TO HELP…OR

4. Indicators
These are chemicals that change colour to show whether a substance is an acid or a base
Common indicators:
Litmus paper
Universal indicators
PH meters
It is important to monitor pH especially in pools – look at page 17 of your booklet/pg 60 of the text
Red cabbage indicator practical

5. *A base can neutralise an acid pg 78
It removes the H+ ions and converts them to water.
For example:
Sodium hydroxide + Hydrochloric Acid -> Sodium Chloride + Water
(base) (acid) Na+Cl- + H2O
Sodium Chloride is commonly called what?

6. Points to Remember!
Any substance that can neutralise an acid is called a base.
Neutralisation always produces a salt.
There are neutralisation reactions which occur everyday:
*Insect Stings *Soil treatment
*Indigestion *Factory waste