8. Characteristics of Bases:
Bases usually taste bitter
Bases feel slippery
Bases contain hydroxide ions
STRONG bases are also poisonous
and corrosive to skin
OH-
9. Strong Bases The Formulae
Lithium hydroxide
Sodium hydroxide
Potassium hydroxide
Rubidium hydroxide
Caesium hydroxide
Barium hydroxide
Calcium hydroxide
Strontium hydroxide
LiOH
NaOH
KOH
RbOH
CsOH
Ba(OH)2
Ca(OH)2
Sr(OH)2
Common Bases:
(Hydroxides of Group 1 and Group 2 Metals
are STRONG)
All others are WEAK
11. Reactions between
acids and bases
When and acid and a base
react with each other, the
characteristic properties of
both are destroyed. This is
called neutralization.
12. Reactions between
acids and bases
General formula for acid base reaction:
Acid + Base → H2O + Salt
“Salt” means any ionic
compound formed from
an acid/base reaction
NOT JUST
NaCl !!
Neutralization Reaction Animation
15. Indicators
An indicator is a compound
that will change color in the
presence of an acid or base
Universal indicator (pH paper)
Used for the full pH range
Red Litmus-Turns blue in base
Blue Litmus-Turns red in acid
Phenolphthalein-Turns pink
in base
16. pH
pH stands for “potential
hydrogen” and is a measure
of how many H+ ions there
are in solution.
The MORE H+ there are, the
LOWER the pH will be.
17. pH Scale
Shows the range of H+
concentrations
High H+ concentration Low H+ concentration