Reaction RatesBy: Jorden Kulhanek

AndDJ Hart

Rate of Reaction

The rate of a reaction is the speed at which a reaction happens.

If a reaction has a low rate, that means the molecules combine at a slower speed than a reaction with a high rate

Collision TheoryThere is another big idea for rates of

reaction called collision theory.

The collision theory says that as more collisions in a system occur, there will be more combinations of molecules bouncing into each other.

Collision frequency Frequency of collision. The average number of collisions that a molecule undergoes each second.

How Rates Of Reaction Work With Collision Theory

Rates of reaction works with the collision theory by measuring the rate of speed of molecules colliding with eachother.

Concentration Concentration is if

there is more of a substance in a system, there is a greater chance that molecules will collide and speed up the rate of the reaction.

If there is less of something, there will be fewer collisions and the reaction will probably happen at a slower speed.

Temperature When you raise the

temperature of a system, the molecules bounce around a lot more because they have more energy.

When they bounce around more, they are more likely to collide.

When you lower the temperature, the molecules are slower and collide less.

And the rate of colliding is lower. And less chance of it happening.

CatalystsA substance that

increases the rate of a reaction but is not consumed in the reaction.

It does so by lowering the activation energy of a reaction

Pressure

Pressure affects the rate of reaction.

When you increase the pressure, the molecules have less space in which they can move.

That greater density of molecules increases the number of collisions.

When you decrease the pressure, molecules don't hit each other as often. The lower pressure decreases the rate of reaction.

OrderThe order of a reaction is the sum of concentration exponents in the rate law for the reaction.

Rate constantA rate constant is a proportionality

constant that appears in a rate law.

A rate law or rate equation relates reaction rate with the concentrations of reactants, catalysts, and inhibitors.

Activation energyThe minimum

energy required to convert reactants into products

The activation energy can be determined from reaction rate constants at different temperatures by equations.

Quiz 1.What works with the collison theory by measuring the rate of speed of molecules colliding?

2.What is the speed at which a reaction happens? 3.What is another big idea for rates of reaction? 4.When molecules bounce around what are they more

likely to do? 5.What happens to the molecules when the temp. is

low? 6.What happens when you increase the pressure? 7.Greater density of molecules does what? 8. what is a substance that increases the rate of a

reaction but is not consumed in the reaction? 9.whats it called when there is more of a substance in

a system? 10.What is the sum of concentration exponents called?

Answers1.Rate of reaction2.Rate of reaction3.Collison theory4.Collide5.They are slower and collide less6.Molecules have less space to move7.Increase in collisions8.catalysts 9.Concentration10.Order

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