Notes Enzymes:

What must occur for a reaction to proceed?
Collision Theory:
1. Reactants must collide
2. Reactants must have enough energy
3. Reactants must hit with proper orientation

Here is morbid example of collision theory. How do a train and school bus react to give a train with engine damage and a school bus in two pieces?
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If you look back to the three conditions required for a reaction to occur, we can relate them to his terrible accident. In the collision theory, condition number one requires that the train must collide with the bus. Condition number two requires that the train and bus collide with enough energy for the reaction to occur, meaning the train must hit bus with enough energy, not merely tap the bus. The third condition requires that the train and bus hit with the proper orientation. If the bus hit the side of the train, it will not slice the train in have. The train must t-bone the bus. Hopefully this visual will help you to remember the condition required for a reaction to occur.

Energy Diagrams:
Energy diagrams are also called reaction progress diagrams as they depict the energy of the chemicals involved in the reaction through out the course of the reaction.

The following is an example of an exothermic reaction:

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A catalyst will lower the activation energy of a reaction. The result is shown in the following reaction progress diagram for an exothermic reaction.
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The green line in the transition state is showing the new barrier energy, the new amount of activation energy needed for this reaction to occur. This reaction has a significantly higher probability of happening as the energy it needs to over come has decreased.

Enzyme: increase the rate of a reaction without itself being used up, a biological catalyst
Substrate: the substance being acted on

Reaction rates are dictated by:
1.