kinetics Flashcards
rate equation
rate = change in conc / time
unit for rate of reaction…
mol dm-3 s-1
what must particles do in order to react?
collide with:
- sufficient energy (Ea)
- correct orientation
what are the 5 factors that affect rate of reaction?
- temperature
- pressure
- concentration
- surface area
- catalyst
Activation Energy is…
The minimum energy required for successful collisions to result in a reaction
Maxwell-Boltzmann Distribution is…
a diagram showing that no particles at any one time have 0 energy.
- It also shows that there are only a few particles that meet the activation energy and those that surpass it will be able to complete a reaction
what’s Adsorption
The gasses form weak bonds with the metal catalyst, holding the molecules in place. The gasses react on the surface
what’s Desorption?
The products break away from the metal surface which leaves room for more reactants to form weak bonds with the metal
The affect that occurs to a Maxwell-Boltzmann curve when a catalyst is added
Activation Energy Lowers
The affect that occurs to a Maxwell-Boltzmann curve when the temperature of the particles is increased
Peak lowers and shifts to the right. Number of Particles Exceeding Activation Energy Increases
Increasing Temperature
The particles have a higher kinetic energy, this gives them more energy as a whole which increases the amount of particles that have E=Ea or above.
Increasing Pressure
There are more particles in a given volume so the likelihood of successful collisions increases as there is less free space
Increasing Surface Area
This disperses the mass of a substance so that there are more particles in a given area without changing the mass of the substance. This increases the likelihood of successful collisions.
Collision frequency
number of collisions between particles per second
a catalyst is…
Lowers the Ea of a reaction by taking an alternate pathway. It takes part in the reaction without itself being chemically
changed (or used up) at the end of the reaction
