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When a catalyst is involved in the collision between the reactant molecules, less energy is required for the chemical change to take place, and hence more collisions have sufficient energy for reaction to occur. The reaction rate therefore increases.Collision theory is closely related to chemical kinetics.hen a catalyst is involved in the collision between the reactant molecules, less energy is required for the chemical change to take place, and hence more collisions have sufficient energy for reaction to occur. The reaction rate therefore increases. Collision theory is closely related to chemical kinetics.
Imagine the building blocks are right in front of you on the table. Sometimes we use our chemistry toys to help us visualize the movement of the atoms. We plug and unplug the little connectors that represent chemical bonds. There are a few key points you should know about chemical reactions: 1. A chemical change must occur. You start with one molecule and turn it into another. Chemical bonds are made or broken in order to create a new molecule. One example of a chemical reaction is the rusting of a steel garbage can. That rusting happens because the iron (Fe) in the metal combines with oxygen (O 2) in the atmosphere. Chemical bonds are created and destroyed to finally make iron oxide (Fe 2 O 3). When a refrigerator or air conditioner cools the air, there is no reaction in the air molecules. The change in temperature is a physical change. When you melt an ice cube, it is a physical change. When you put bleach in the washing machine to clean your clothes, a chemical change breaks up the molecules in your stains. 2. A reaction could include atoms, ions, compounds, or molecules of a single element. You need to remember that a chemical reaction can happen with anything, just as long as a chemical change occurs. If you put pure hydrogen gas (H2) and pure oxygen gas in a room, they might be involved in a reaction to form water (H2O).