Which of the following reactions describes a process that involves homogeneous catalysis?
The hydrolysis of aqueous ethyl methanoate using a dilute hydrochloric acid catalyst
The dehydration of gaseous ethanol to form ethene over a heated solid aluminium oxide catalyst
The hydrogenation of gaseous ethene to ethane using a finely divided solid nickel catalyst
The reduction of gaseous nitrogen monoxide by carbon monoxide gas over a solid platinum catalyst