What is ? Collision theory? Rate of reaction Activation energy? Factors affecting? Collision theory? Rate of reaction Activation energy? Energy level diagram? Effective collision?

Quiz Using collision theory, explain how these factors affect the rate of reaction Size of reactant Temperature Concentration Catalyst 2) Draw activation energy with and without catalyst

What is the rate of a reaction The rate of reaction is how quickly a reaction happens. Slow reaction Fast reaction

Iron rusting - a CHEMICAL REACTION with a slow reaction rate. Wood burning - a chemical reaction with a fast reaction rate.

What is ? Collision theory? Rate of reaction Activation energy? Factors affecting? Collision theory? Rate of reaction Activation energy? Energy level diagram? Effective collision?

"You can’t react if you don’t collide." collision theory "You can’t react if you don’t collide."

3 necessary requirements in order for a reaction to take place: the particles must collide to react. 2. Collision of particles must produce enough energy (to overcome energy of activation) 3. Collisions of particles must be correctly oriented

What is ? Collision theory? Rate of reaction Activation energy? Factors affecting? Collision theory? Rate of reaction Activation energy? Energy level diagram? Effective collision?

Prevent Effective collision Camera to detect fast moving traffic

Effective collision

What is ? Collision theory? Rate of reaction Activation energy? Factors affecting? Collision theory? Rate of reaction Activation energy? Energy level diagram? Effective collision?

Activation energy The energy that must be overcome in order for a chemical reaction to occur Activation energy is the minimum energy necessary for a specific chemical reaction to occur

Activation energy The sparks generated by striking steel against a flint provide the activation energy to initiate combustion in this Bunsen burner.

A little activation energy is added with the aid of a weed burner... What is activation energy A little activation energy is added with the aid of a weed burner...

Not enough kinetic energy for reactants to leap over reaction barrier. What is activation energy A "hot" reaction in progress showing reactants leaping over the activation energy barrier Not enough kinetic energy for reactants to leap over reaction barrier.

Activation energy

Activation energy

What is activation energy Only collisions with enough energy react to form products. The critical amount of energy to make the reaction proceed

A + B  C + D reactants products

What is activation energy

What is ? Collision theory? Rate of reaction Activation energy? Factors affecting? Collision theory? Rate of reaction Activation energy? Energy level diagram? Effective collision?

What affects the rate of a reaction? Size of reactant Temperature of reaction mixture Concentration of reactants /pressure catalyst

What affects the rate of a reaction? 1. The effect of size of reactant

1. The effect of size of reactant

THE EFFECT OF SIZE OF REACTANT a reaction between magnesium metal and a dilute acid like hydrochloric acid. Increasing the number of collisions per second increases the rate of reaction.

THE EFFECT OF SIZE OF REACTANT Magnesium metal

THE EFFECT OF SIZE OF REACTANT Magnesium metal

1. The effect of size of reactant Reducing the size of reactant increases the Total Surface Area increases the frequency of collisions between particles Increase the frequency effective collisions between particles Increase the rate of reaction.

Increasing temperature will increase kinetic energy in the particles

1. The effect of temperature Increase the temperature of solution increase the kinetic energy of particles increase the frequency of collisions between particles Increase the frequency effective collisions between particles Increase the rate of reaction.

3. Concentration and Pressure Increasing concentration or pressure increases the number of particles per unit volume

1. The effect of concentration Increase the concentration of solution increase the number of particles per unit volume increase the frequency of collisions between particles Increase the frequency effective collisions between particles Increase the rate of reaction.

Properties of Catalysts A catalyst will change the rate of a reaction. - The catalyst itself does not take part in the reaction - It is not changed by the reaction it is not used up during the reaction. - A catalyst is usually a transition metal, a transition metal oxide

How does a catalyst work? Provides a surface on which the reaction can take place. This increases the number of collisions between the particles of the substances that are reacting.

4. Catalyst Often a catalyst is there to provide a favourable surface for a reaction to take place The black object represents the catalyst

Decomposition of hydrogen peroxide manganese(IV) oxide, MnO2 Examples CATALYSTS reaction catalyst Decomposition of hydrogen peroxide manganese(IV) oxide, MnO2 Manufacture of ammonia by the Haber Process iron Contact Process to make sulphuric acid vanadium(V) oxide, V2O5

A catalyst provides an alternative route for the reaction with a a lower activation energy.

Activation energy with no catalyst

Activation energy with catalyst

4. The effect of catalyst Catalyst provides alternative route That has a lower activation energy So more particles have energy equal or greater than activation energy. Number of effective collisions increase. Increase the rate of reaction.

What is ? Collision theory? Rate of reaction Activation energy? Factors affecting? Collision theory? Rate of reaction Activation energy? Energy level diagram? Effective collision?

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