Products and Reactants

[Maya Pakulski 1D]

When finding K or Q like in the 6N problems, how do we know what the products and reactants are? Do we look at the final combined equation after finding the half reactions?

[Abigail Sanders 1E]

Yes, what I do is I write out the half reaction for each oxidation or reduction reaction and then make sure I flip it if necessary so that the electrons cancel and it is in the right oxidation/reduction form. Then, I combine the two balanced half-reactions for the overall reaction for the cell and determine the reactants and products from that equation.

[Keya Jonnalagadda 1A]

Yes, the final combined reaction (after the electrons have been cancelled) is the reaction you use to find Q. K is usually given in the problem, or when equilibrium concentrations for the species in the final combined reaction are given, you can solve for K. The formula is [products]/[reactants] for both Q and K.

[DLee_1L]

Just to clarify, when calculating Q and K, we combine the concentration and partial pressures? or is there some conversion we have to do?

[Leslie Almaraz 4G]

I think it depends on the classification of the question

[Kayli Choy 2F]

Just to clarify, when calculating Q and K, we combine the concentration and partial pressures? or is there some conversion we have to do?

Yes, as long as all concentrations are in M, and partial pressures are in atm.