2. Rate of reaction
 Rate of reaction is the measurement of
the speed which reactants are converted into
products in a chemical reaction / change in a
selected quantity during a reaction per unit
time.
 Average rate of reaction is the average value of
the rate of reaction over an interval of time.
 Instantaneous rate of reaction / Rate of
reaction at a given time are the actual rate of
reaction at that instant.

4.  Total surface area of solid reactant
 Concentration of reactant
 Temperature of reactant
 Use of catalyst
 Pressure of gaseous reactant

7.  Take note :

8.  The smaller the size (increase the total surface
area), cm3, of the solid reactant, the higher the rate
of reaction, cm3 s-1 or cm3 min-1.
 Explanation:

9. Effect of concentration of a liquid
reactant on the rate of reaction
The higher the concentration, mol dm-3, of a
liquid reactant, the higher the rate of
reaction, mol dm-3 s-1 or mol dm-3 min-1.

12.  Increase in temperature, the higher the rate
of reaction.

13.  Alters the rate of reaction
 It is specific in its action. It can only catalyse a
particular reaction
 Does not change the quantity of products formed
 Only small amount of catalyst is needed to increases
the rate of reaction. (An increase in the quantity of
catalyst will increase the rate of reaction but only a
very slight increase.)
 Catalyst remains chemically unchanged but may
undergo physical changes.

16. (catalyst)

18. catalyst

19. Effect of pressure on the rate of
reaction
• Increase in pressure, the higher the rate of
reaction (reversible reaction and gaseous
reactants and gaseous product).

21. 1.3 Collision Theory
• According to kinetic theory of matter : Particles of matter are
in continuous motion & constantly in collision with each other.
• Collision theory states a reaction occur when the particle of
the reactant collide with each other with
the correct orientation and achieve activation energy.
• Collision theory also states that the rate of reaction can be
determined by frequency of collision / number of collisions
per second & magnitude of Ea.
• Collision which achieve a minimum amount of activation
energy & with correct orientation will result in reaction.
(Effective collision)
• Ineffective collision is the particles that collide with
energy less than activation energy or wrong orientation.

22. Activation energy, Ea
• The energy barrier that must be overcome by
the colliding particles of the reactants so that
the reaction can occur.
• Can be visualized by sketching the energy
profile diagrams.