# Collision Theory

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• Created by: joshd
• Created on: 02-04-14 13:21
What does the collision theory say?
That the rate of a reaction depends on how often and how hard the reacting particles collide with each other. The basic idea is that particles have to collide in order to react, and they have to collide hard enough.
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What happens when the temperature increases and what does this mean? (e.g, speed)
When the temperature is increased, the particles all move quicker. If they're moving quicker, they're going to have more frequent collisions.
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What happens if a solution is made more concentrated? What does this make?
If made more concentrated, it means there are more particles of reactant knocking about between the water molecules. This makes collisions between the particles more likely.
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What happens in a gas with a higher concentration?
In a gas, increasing the pressure means the particles are more squashed up together so there are going to be more frequent collisions.
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What happens if one of the reactants is a solid? What does this mean?
Then breaking it up into smaller pieces will increase its surface area. This means the particles around it in the solution will have a larger area to react with, so there'll be more frequent collisions.
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How does a solid catalyst work? What do they increase?
A solid catalyst works by giving the reacting particles a surface to stick to. They increase the number of successful collisions by lowering the energy particles need to start reacting with each other.
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How are faster collisions caused?
Faster collisions are ONLY caused by increasing the temperature.
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When do reactions only happen? Why?
If the particles collide with enough energy. This is because there's a minimum energy needed to break the initial bonds.
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What happens at a higher temperature?
At a higher temperature, there will be more particles colliding with enough energy to make the reaction happen.
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## Other cards in this set

### Card 2

#### Front

What happens when the temperature increases and what does this mean? (e.g, speed)

#### Back

When the temperature is increased, the particles all move quicker. If they're moving quicker, they're going to have more frequent collisions.

### Card 3

#### Front

What happens if a solution is made more concentrated? What does this make?

### Card 4

#### Front

What happens in a gas with a higher concentration?

### Card 5

#### Front

What happens if one of the reactants is a solid? What does this mean?