Collision Theory

TKU 3023 INFORMATION AND COMMUNICATION TECHNOLOGY IN CHEMISTRY TITLE: COLLISION THEORY (SIMULATION) NAME

MATRIK NO.

PROGRA MME

SEMESTE R

MOHD ANWAR BIN ALWI

D20081032287

AT16

3

MUHAMAD ZULHELMI BIN AKMEN

D20081032378

AT16

3

COLLISION THEORY Based on the kinetic theory of matter, the particles in matter (gas) will always moving and collide each other. When the temperature is high, the particles have high kinetic energy that causes them to move and collide more frequent. The particles of reactions (atoms, molecules or ions) need to be contacted to each other to let the making and breaking bonds process to occur. Therefore, particles need to collide each other so that the reaction can take places. •

Effective collision – the collision that produces reaction by reaching enough minimum energy with correct orientation. Total energy for particles’ collision must be same or larger than activation energy.

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Activation energy – the minimum energy required for the particles that collide to let the reaction to occur and give product of reaction. Each reaction gives different value of activation energy. Activation energy is needed to break the bond and produce new bonding in a reaction. The reaction with high activation energy occurs in slow rate compare to the reaction with lower activation energy.

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Effective collision frequency – number of collision occur in one second. Effective collision frequency can affect the rate of reaction. The reaction depends on how often the effective collision occurs. If the effective collision frequency is high the rate of reaction also high and oppositely, if the effective collision frequency is low, the rate of reaction will be low as well.

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Factors affecting rate of reaction related to collision theory:

1. Effect of surface area– when size is small, total surface area for the reaction increase. So, the chances for collision also increase (effective collision frequency increase) making the rate of reaction to increase.

2. Effect of pressure – for reaction involving gas, when pressure increase, the particles of gases will be compressed to fill smaller space. The number of gas particles per unit volume increase. The collision chances also increase (effective collision frequency increase) and increasing rate of reaction.

3. Effect of concentration – more concentrated mean that more particles exist per unit volume. This cause the particles to have more chances to collide each other ( increasing effective collision frequency) and rate of reaction will increase.

4. Effect of temperature – when temperature increase, the particles’ kinetic energy increase making the particles moving faster and increasing the effective collision frequency ( rate of reaction increase)

5. Effect of catalyst – when positive e catalyst is used, it will give alternative reaction path that required lower activation energy for the reaction to occur. More particles that collide will have new lower activation energy and increasing the effective collision frequency. As the result, the rate of reaction will increase too. ENGAGE

The boiling process (direct heat provided)

The evaporation process of sea water by the sun

1. What is the different in both processes? 2. What is the changes of state of matter in the process? 3. Which process takes the faster time to complete? 3. What factor that effect the process to occur faster and increasing the rate of reaction in above process?

EMPOWER STEPS 1. Particles need to collide to each other in order for the reaction to occur. 2. Effective collision will only occur if the particle’s collision has the same or larger activation energy and in correct orientation to produce reactions. 3. Factors affecting rate of reactions related to the collision theory: 1. Effect of surface area 2. Effect of pressure 3. Effect of concentration 4. Effect of temperature 5. Effect of catalyst 4. Log on to the website provided to observe more on collision theory. RESULT 1.http://www.chem.uci.edu/undergrad/applets/sim/simulation.htm

The movement of particles (chemical kinetics) 2. http://www.chemguide.co.uk/physical/basicrates/introduction.html

The Concept Of Collision Theory

Orientation Of Particles

Activation energy

3. http://www.youtube.com/watch?v=VbIaK6PLrRM

Activation Energy

4. http://www.chm.davidson.edu/vce/kinetics/ReactionRates.html

Effect of Concentration

5. http://www.sinauer.com/cooper/4e/animations0301.html

Effect of Catalyst

Effect of Enzyme (Catalyst)

Question 1. What are the specifications of collision that can lead to effective collision?

2. What is activation energy? 3. What happens to the reaction if the concentration is lowered? 4. How catalyst can affect the rate of reaction? Answer: 1. Effective collision can occur if two condition is obeyed that is the collision energy is the same or greater to the activation energy and the collision must be in correct orientation. 2. Activation energy is the minimum energy required for the particles that collide to let the reaction occur and give the product of reaction. 3. When the concentration is lowered, the particles exist per unit volume will decrease. So, the chance for the particles to collide each other will also decrease. This will cause the effective collision frequency to be lowered and decreasing the rate of reaction. 4. The catalyst provided the alternative pathway for the reaction that will cause the lowering of the activation energy. Therefore, more particles that collide will have new lower activation energy and increasing the effective collision frequency. So, the rate of reaction will also increase.

ENHANCE

Answer all the questions. Objective Questions 1. Which of the way that is used to determine the rate of reaction? A. Measure the temperature of the reaction B. Measure the amount of the reactant C. Measure the product that produces in a unit time D. Measure the total product produce 2. The solution of Sodium Tiosulphate react with Hydrocloric acid to form Sulphur. The addition in the concentration of Sodium Tiosulphate will increase the rate of reaction in forming Sulphur because A. The temperature of mixture is increase B. The kinetics energy of its ion is increase C. The activation energy for the reaction decrease

D. The number of ion per unit volume is increase 3. For the reaction involving gases, the rate of reaction will increase if the pressure is increase. This is because A. The activation energy is increase B. There are more particles per unit of volume of the gas C. The kinetic energy of the reactant increase D. The temperature in the container of the reactant is increase Subjective Questions 4. What is the effect when cooking in high pressure pot compare to normal pot? 5. Which one will melt faster; small size of ice or larger size of ice. Why? 6. How refrigerator function in order to keep the food from damaging? 7. Draw the graph of activation energy versus time to differentiate the condition of reaction in normal process and the reaction in existence of catalyst.