Some questions about heterogenic catalysis

[agargento]

Homework Statement

1. Do the molecules "seek" specific spots on the surface?

2. The main challange in making ammonia is getting over the reaction barrier for N and H.

3. As the temperature rises the mobility of the molecules on the surface increases.

4. The catalytic converter in cars lowers the barrier for the reaction CO -> C + O

Thanks!

Homework Equations

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The Attempt at a Solution

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I'm not sure about my answers. Keep in mind the answers are super-general and are true\false statements, and there's no need to go into much depth. I couldn't find any source for most of these so this is why I'm asking for guidance here. Thanks!

1. From what I understood - yes. They go to spots where they are not bonded to strong to the surface but also not too weak to it.

2. I think this statement is false. the main barrier is breaking the N2 bond and not getting N and H to react.

3. I think this is correct, doesn't need much explanation.

4. This one I'm unsure - is it correct or does the converter lowers the barrier for breaking the O2 ?

 

[nate808]

1. This statement is partially correct. Molecules do have a tendency to bond to specific spots on a surface, but this is not the only factor that determines their location. Other factors such as temperature, pressure, and surface chemistry also play a role.

2. This statement is partially correct. While breaking the N2 bond is a major challenge in ammonia synthesis, getting N and H to react is also a significant barrier. This is because the reaction is highly exothermic and requires precise control to prevent the formation of unwanted byproducts.

3. This statement is correct. As temperature increases, the kinetic energy of the molecules also increases, allowing them to move more freely on the surface.

4. This statement is partially correct. While the catalytic converter does lower the barrier for the reaction of CO to form C and O, it also lowers the barrier for other reactions, such as the oxidation of CO to CO2.