Combustion of gasoline in automobiles produces poisonous gases. Catalytic converters that contain solid platinum, palladium, and rhodium change these poisonous gases into harmless gases. Which statement describes the catalyst?

The platinum, palladium, and rhodium are solid, while the reacting gases are gases, so the catalyst is heterogeneous. A catalyst speeds up a reaction by providing an alternative pathway with lower activation energy. It is not used up by combining with the poisonous gases, and it does not increase the energy needed for the reaction.

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