Catalyst Question 19 Week 9&10 Hw

[605988349]

Hi,

Can anyone explain to me this question:

How are the following aspects of a reaction affected by the addition of a catalysts.
- activation energy of the forward reaction
- activation energy of the reverse reaction
- rate of the forward reaction
- rate of the reverse reaction

What other specified of a catalysed reaction are different from the uncatalyzed reaction
- delta H rxn
- the mechanism
- the overall reaction


Can anyone please go over this problem for me and explain the reasoning for each answer. I'm a bit confused on this topic and what to get an idea of how I did on this part of the exam. Thank you!

[PranavKetharam]

Hi,

Can anyone explain to me this question:

How are the following aspects of a reaction affected by the addition of a catalysts.
- activation energy of the forward reaction
- activation energy of the reverse reaction
- rate of the forward reaction
- rate of the reverse reaction

What other specified of a catalysed reaction are different from the uncatalyzed reaction
- delta H rxn
- the mechanism
- the overall reaction


Can anyone please go over this problem for me and explain the reasoning for each answer. I'm a bit confused on this topic and what to get an idea of how I did on this part of the exam. Thank you!

Hello! A catalyst will reduce the activation energy for both the forward and reverse reactions. Thus, both the rates of the forward and reverse reactions will increase as well. Additionally, catalysts will not affect the delta H nor change the overall chemical reaction, but the mechanism will change due to the presence of a different pathway.

[905960080]

For the activation energy of the forward reaction, the addition of a catalyst lowers it because it helps progress the reaction by lowering the energy required to overcome the transition state, like a bond breaking. For the reverse reaction, the addition of a catalyst does the same thing by changing the transition state. For the rates of reactions, the addition of a catalyst will increase the rates because when there is a lower energy barrier to overcome, more species in the reaction will be able to interact with enough energy to overcome the activation energy and form the product. For the delta H change, a catalyst does not change the deltaH for a reaction because it is simply the energy difference between the products and reactants, catalysts will only ever change an energy barrier. For the mechanism, a catalyst can change this by making the reaction undergo a different pathway so that the activation energy is lower, thus increasing the rate of reaction. For the overall reaction however, the catalyst will be present in the beginning and end and even change the mechanism, but a catalyst will never change the net equation, products and reactants on either side with always be the same with a catalyst or not.

[405972194]

Catalyst are essentially used for the whole purpose of making a reaction occur faster and it does that by lowering the activation energy required for a reaction to run by providing an alternative pathway. Therefore since the activation energy of the entire reaction is lowered, the total activation energy required for the reaction is decreased in both the forward and reverse reaction. Since the activation energies are lowered, the rate of both the forward and reverse reaction would increase since the reaction as a whole will now occur faster.