Select the correct answer.
How would adding the catalyst nitrogen monoxide (NO) affect this reaction?
[tex]2 SO_2(g)+O_2(g) \rightarrow 2 SO_3(g)[/tex]
A. NO increases the rate at which [tex]SO _3[/tex] molecules are formed.
B. NO reacts with [tex]SO _3[/tex] to produce more [tex]SO _2[/tex] molecules.
C. NO decreases collisions between the [tex]SO _2[/tex] and [tex]O _2[/tex] molecules.
D. NO increases the concentration of the [tex]SO _2[/tex] and [tex]O _2[/tex] molecules.
E. NO increases the activation energy of the [tex]SO _2[/tex] and [tex]O _2[/tex] molecules.
Answer (1)
Catalysts increase the rate of reaction.
Catalysts provide an alternative reaction pathway with lower activation energy.
Catalysts do not change the concentration of reactants or products.
Therefore, NO increases the rate at which S O 3 molecules are formed. A
Explanation
Understanding the Role of a Catalyst The question asks about the effect of adding a catalyst, nitrogen monoxide (NO), to the reaction 2 S O 2 ( g ) + O 2 ( g ) i g h t ha r p oo n u p 2 S O 3 ( g ) . We need to identify the correct statement describing the catalyst's role.
Key Properties of Catalysts A catalyst speeds up a chemical reaction by providing an alternative reaction pathway with a lower activation energy. It does not change the equilibrium position of the reaction, nor does it affect the concentrations of the reactants or products.
Evaluating the Options Based on the properties of catalysts, we can evaluate the given options:
A. NO increases the rate at which S O 3 molecules are formed. - This is consistent with the role of a catalyst. B. NO reacts with S O 3 to produce more S O 2 molecules. - This is not a typical behavior of a catalyst. C. NO decreases collisions between the S O 2 and O 2 molecules. - Catalysts don't generally affect collision rates directly. D. NO increases the concentration of the S O 2 and O 2 molecules. - Catalysts don't change reactant concentrations. E. NO increases the activation energy of the S O 2 and O 2 molecules. - Catalysts decrease activation energy.
Conclusion The correct answer is A because a catalyst increases the rate at which the product ( S O 3 ) is formed by lowering the activation energy of the reaction.
Examples
Catalysts are used extensively in the chemical industry to speed up reactions and make them more efficient. For example, in the production of ammonia via the Haber-Bosch process, an iron catalyst is used to increase the rate of reaction between nitrogen and hydrogen. Similarly, catalytic converters in cars use catalysts like platinum, palladium, and rhodium to convert harmful pollutants in exhaust gases into less harmful substances like carbon dioxide, water, and nitrogen. Understanding how catalysts work helps in designing more efficient and environmentally friendly chemical processes.
