Effects of catalysts on RofR Flashcards
What is meant by activation energy for a reaction ?
The minimum energy particles require in order to start a reaction by breaking chemical bonds
What does the transition state describe ?
The stage where bonds are in the process of breaking but simultaneously bonds ae also in the process of forming
Is the transition state stable or unstable ?
Unstable
What does the transition state go on to form ?
The products
What is meant by the activation energy ?
The enthalpy difference between the reactants and the highest pointbon the curve.
What does the highest point of the curve represent?
The transition state
What will happen at a low activation energy at room temp ?
Reaction could take place rapidly at room temp
- because at room temp, a relatively large proportion of reactant molecules will collide with enough energy to cross the activation energy barrier and react
What will happen at a high activation energy at room temp ?
Reactiln will be relatively slow at room temp
- because only small proportion of reactant molecules will collide with enough energy to cross the activation energy barrier
State a way to increase rate of chemical reactions?
Use a catalyst
How do catalyst work in increasing the rate of chamical reactions?
Catalyst allow a reaction to take place via an alternative reaction pathway with a lower activation energy than the uncatalysed reaction
How can catalysts be reused ?
Because catalysts are not used up in the reaction and are not permanently changed
Economical advantage
By using a catalyst, we can make a chemical reaction take place rapidly even at relatively low temps
- this reduces the amount of energy needed by the chemical industry which in turn reduces the need to burn fossil fuels to provide this energy
- this saves money providing an economic benefit
It also reduces co2 emissions, makimg the chemical industry more sustainable
Disadvantage of catalysts
Some catalysts are toxic