5 - Kinetics Flashcards
What is Collision Theory
For a reaction to occur between two particles, they must collide with enough energy to break their bonds
How does temperature affect the Collision Theory
An increase in temperature increases the speed of the molecules which in turn increases both their energy and the frequency of collisions
How does the concentration affect Collision Theory
If there are more particles in a given volume then the frequency of collisions will increase, but as the reactants are used up, the concentration falls so the frequency of collisions fall as well
How does pressure affect Collision Theory
Increase pressure, increase the number of collisions
How does surface area affect Collision Theory
The greater the total surface area of a solid, the more of its particles are available to collide with molecules in a gas or a liquid, which means that breaking lumps into smaller piece increase the rate of the reaction, as there are more sites for reaction
Define a catalyst
A substance that can change the rate of a chemical reaction without being chemically changed itself.
Define Activation energy
the minimum energy to form a transition state for a reaction to occur
Describe the effect of increasing temperature on a Maxwell-Boltzmann graph
the Peak decreases and moves to the right
How do catalysts work
They provide a different pathway for the reaction, one with a lower activation energy
How do catalytic converters work
The gasses form weak bonds with the metal atoms of the catalyst which is called adsorption. Then the gases reaction on the surface.
after this they break away from the metal which is called desorption.
