Finding K

[Mya Majewski 1L]

When given the K of the reverse reaction and concentrations of the forward. How do you find the overall K? Also, how do you know whether the reaction is favoring the products or the reactants?

[Chem_Mod]

Could you give an example in which the problem is like what you are describing?

[Charlene Tang 1B]

I'm going to assume the K for the overall reaction is the K for the forward reaction.

If you're given the K (equilibrium constant) for the reverse reaction, all you need to do is just 1/K_reverse to get the K_forward.

If K is large (or just >1), then concentration of the products is larger than that of the reactants (since K=[products]/[reactants]), and we can assume that product formation (or the forward reaction) is favored. If K is small (<1), then the concentration of reactants is larger than that of the products. So reactant formation is favored and the reverse reaction is favored.

Hope this helps!