Multistep reactions

[pmokh14B]

Do we need to know how to find final equilibrium concentrations for multistep reactions? If so, where can I find examples and solutions?

[Chem_Mod]

This is not part of the Chem 14B syllabus.

[chimerila]

Not to question the all knowing ChemMod (mad respect), but there's a homework problem in the syllabus that is as follows:

"For the reaction N2(g) + 3 H2(g) = 2 NH3(g) at 400. K, K = 41. Find the value of K for each of the following reactions at the same temperature:
(a) 2 NH3(g) = N2(g) + 3 H2(g)
(b) 1/2 N2(g) + 3/2 H2(g) = NH3(g)
(c) 2 N2(g) + 6 H2(g) = 4 NH3(g)"
*imagine the equal signs are actually equilibrium notations, I can't figure out how to type it*

I could be misunderstanding what the problem is asking, but wouldn't we need to know how to do multistep reactions to solve this problem? And are multistep reactions the same as composite equations, because that was also kind of unclear to me in the textbook.

[chimerila]

I also wonder the same thing about 5H.3, as that problem seems to be requiring a similar method to solve it. Any clarification on this would be greatly appreciated

"Use the information in Table 5G.2 to determine the value of K at 300 K for the reaction 2 BrCl(g) + H2(g) = Br2(g) + 2 HCl(g)."
*again, equal sign is actually equilibrium arrows/notation*

[jisulee1C]

For the problem given it's not a multistep reaction. In fact, you are asked to manipulate the K of the given chemical reaction to find the other K values. For example A since the reaction is reversed you would find the inverse of the given K to find the new K value for the new reaction.

[chimerila]

For the problem given it's not a multistep reaction. In fact, you are asked to manipulate the K of the given chemical reaction to find the other K values. For example A since the reaction is reversed you would find the inverse of the given K to find the new K value for the new reaction.

Ahhh, I see. So for A, would it be K = 1/41?

[jisulee1C]

Yep. The K would be 1/41 because that's the inverse.