Catalysts

Question 1

what are catalysts?

Answer 1

catalysts increase the reaction rate without being used by the overall reaction

Question 2

what is the role of catalysts?

Answer 2

• increase reaction rate by providing an alternative route with a lower activation energy

Question 3

what are the types of catalysts?

Answer 3

• homogenous catalysts
• heterogenous catalysts

Question 4

what are homogenous catalysts?

Answer 4

homogenous catalysts have the same physical state as the reactants

Question 5

what is the process of homogenous catalysts?

Answer 5

• catalysts react with the reactants to form an intermediate
• the intermediate then breaks down to give the product and regenerated the catalyst

Question 6

what are heterogenous catalysts?

Answer 6

heterogenous catalysts have a different physical state from the reactants

Question 7

what is the process of heterogenous catalysts?

Answer 7

• they are usually solids in contact with gaseous reactants or reactants in solution
• reactant molecules are absorbed(weakly bonded) onto the surface of the catalyst, where the reaction takes places
• after the reaction, product molecules leave the surface of the catalyst, desorption

Question 8

what are benefits of catalysts?

Answer 8

• great economic importance
• increased sustainability by lowering the activation energy, the temperature also lowers
• reduces the energy demand from combustion of fossil fuels with resulting reduction in CO2 emissions

Question 9

what are some weaknesses of catalysts?

Answer 9

• expensive
• some catalysts are toxic