7. Collision Theory states that for a reaction to take place particles must collide with sufficient energy to overcome the Activation energy for that particular reaction
11. What does a real reaction look like ? What is happening to the rate of the reaction with time? How can we find the rate at any instant When is the reaction finished?
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15. Fact 1: An increase in the concentration of a solution, or the pressure of a gas, results in an increase in the reaction rate Explanation : If the concentration of a solution, or the pressure of a gas, is increased, then there are more particles in a given volume. Therefore there will be more collisions in a set amount of time and the probability of more successful collisions becomes higher. As a result the reaction rate will increase.
16. Fact 2: An increase in surface area of a solid results in a increase in the rate of a reaction. Explanation : If the surface area of a solid is increased, there are more particles exposed to the other reactant. Therefore there will be more successful collisions in a set amount of time and the rate increases
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19. Fact 3: An increase in temperature results in an increase in reaction rate. Explanation : If the temperature is increased, the average kinetic energy of the particles increases. There is therefore a greater chance of more collisions having an energy greater than the activation energy and reaction rate increases. Also (less importantly) because particles are moving faster, there will be more collisions in a given time, therby increasing the rate
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24. Fact 4: Addition of a catalyst can lead to an increase in reaction rate Explanation : A catalyst acts by enabling a reaction to proceed via a route of lower activation energy. There will therefore be more collisions of sufficient energy to cause a reaction to occur, and rate will increase