Collision theoryDon't miss out on the latest A1 notes and tips from top Leaving Cert performers!
This accounts for the factors that influence the rate of reaction.
For a reaction to occur the reacting particles must collide with each other.
A collision only results in the formation of products if a certain minimum energy is exceeded in the collision - this is then described as an effective collision.
An effective collision: occurs when bonds are broken and new bonds are formed, bringing about the formation of products.
The rate of reaction depends on the number of e effective collisions per second between reacting particles.
Activation Energy:is the minimum energy that colliding particles must have for a reaction to occur. Denoted Ea.
Low activation energy means a faster rate. Conversely, high activation energy means a slower rate.
increased temperature means that the kinetic energy of the molecules increases. Therefore, more collisions occur and hence more effective collisions must occur.
2. Nature of the reactants:
covalent compounds have to break bonds to react and
therefore they need more energy and so they have a higher activation energy.
3. Particle size:
smaller particles have a larger surface area for more collisions to occur. Therefore, more e ective collisions will occur and hence they will reach the activation energy more rapidly.
greater concentration means more particles and therefore more collisions, and hence more e ective collisions. Thus, the activation energy is reached more rapidly.
it provides an alternative pathway with a lower activation energy.