Answer:

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1.collision theory, theory used to predict the rates of chemical reactions, particularly for gases. The collision theory is based on the assumption that for a reaction to occur it is necessary for the reacting species (atoms or molecules) to come together or collide with one another.

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2.The collision theory explains why reactions occur between atoms, ions, and molecules. ... With an increase in temperature, there is an increase in the number of collisions. Increasing the concentration of a reactant increases the frequency of collisions between reactants and will, therefore, increase the reaction rate.

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3.Catalysts are substances that increase reaction rate by lowering the activation energy needed for the reaction to occur. A catalyst is not destroyed or changed during a reaction, so it can be used again.

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• It seems like you asked this last week right???

• By the way i copy it to my own answer because this question is familiar