Question

1) Consider the truth of each of the following statements and provide corrections where

required.

(a) A catalyst introduces a new reaction pathway with lower enthalpy of activation.

(b) As the Gibbs energy is more favorable for a catalytic reaction, yields of the product

are increased by catalysis.

(c) An example of a homogeneous catalyst is the Ziegler-Natta catalyst made from TiCl4

and Al(C2H5)3.

(d) Highly favorable Gibbs energies for the attachment of reactants and products to a

homogeneous or heterogeneous catalyst are the key to high catalytic activity.

2) What are the differences between Fischer and Schrock carbenes?

3) Indicate in which of the mechanisms discussed in class are not change in the oxidation

state and in which of them there are.