What you’ll learn3 learning objectivesChoose one objective for a focused lesson, or study the complete topic.26.2.1Catalysts can be homogeneous or heterogeneous• Explain that catalysts can be homogeneous or heterogeneousSyllabus objective26.2.2Heterogeneous catalyst action• Describe the mode of action of a heterogeneous catalyst to include adsorption of reactants, bond weakening and desorption of products, e.g.:- (a) iron in the Haber process- (b) palladium, platinum and rhodium in the catalytic removal of oxides of nitrogen from the exhaust gases of car enginesSyllabus objective26.2.3Mode of action of a homogeneous catalyst• Describe the mode of action of a homogeneous catalyst by being used in one step and reformed in a later step, e.g.:: (a) atmospheric oxides of nitrogen in the oxidation of atmospheric sulfur dioxide; (b) Fe 2+ or Fe3+ in the I–/S2O8; 2– reactionSyllabus objective