The hydrogenation of unsaturated hydrocarbons is
an important industrial process. Precious metals,
such as platinum and palladium, can greatly
increase the rate of this reaction. During this
process, the gaseous reactants are pumped
across a layer of metal powder. An example of this
process is shown below.
Describe how the metal probably increases the
reaction rate, identify whether this is an example of
homogeneous or heterogeneous catalysis, and
explain how you know.
(1)

The human activities in two locations are described below: location a: rampant use of plastic containers location b: excessive use of pesticides and fertilizers which statement is most likely true? location a will have poor air quality because plastic is biodegradable. location a will experience water scarcity because plastic absorbs moisture. the population of honeybees will increase in location b because production of crops will increase. the population of fish in location b will decrease because the water is contaminated.