Download 2.8-Reaction Rate

Reaction Rate
To increase the rate of a chemical
reaction:
1) Increase the temperature (molecules
move faster and collide more frequently)
2)
Increase the concentration of the
reactants
3)
Increase the surface area of the
reactants (crushed alka seltzer tablets
will react faster than a solid tablet)
4)
Agitate or stir
5)
Add a catalyst. (Demonstration).
Read page 155.
To slow down a reaction:
1) Add an inhibitor
2)
Do the reverse of above
Work on activity on page 154. Hand in #1, 2
and 1, 2.
types of chemical reactions:
1) Corrosion – the deterioration of metals.
It always occurs in the presence of
oxygen.
Example:
Fe + O2  Fe2O3
Metal + oxygen  (corrosion)
To prevent corrosion in a metal, coat the
metal with zinc. This process is called
galvanization.
2)
Combustion – the rapid exothermic
chemical reaction of a substance and
oxygen. It requires heat, oxygen and fuel
(substance), and results in the release of
heat or light.
a. Examples: fire; bbq; car engine.
Example: burning propane in a bbq
C3H8 + O2  CO2 + H2O + energy (heat)
Propane + oxygen  carbon dioxide + water +
energy
Lab on page 160 “ An illuminating experience”
BLM 2-16
Page 164 #1-8
Page 165 #1-6
Page 170 #1-13, 20, 21, 22, 23