You can write the Keq expression for a chemical reaction by putting products over reactants, coefficients become exponents, and liquids and solids get ignore...
https://yeahchemistry.com/tutorials/chemical-equilibriumhow-find-equilibrium-constant-keq
A system which is not at equilibrium will move spontaneously to a position of being at equilibrium. The same argument that was used for solids can also be used for liquids. Thus, we can expand the last statement: "When we write the K eq expression for a reaction with solids or liquids, we simply leave out the solids and the liquids". included in the K eq expression.
https://yeahchemistry.com/tutorials/chemical-equilibriumhow-find-equilibrium-constant-keq
Calculate Keq, if the [N 2 O 4 ] is 0.00455 M & [NO 2] is 0.031M at equilibrium. Keq = [N 2 O 4] [NO 2]2 = [0.00455] [0.031]2 Keq = 4.73 Same Keq!!! Important! Keq is the same for a given reaction that is: at equilibrium at the same temperature no matter what the initial concentrations were.
https://meanings.co/def/review-how-to-calculate-keq-99649/
Ka = [H+] [A-]/ [HA] pKa = - log Ka at half the equivalence point, pH = pKa = -log Ka
https://www.thoughtco.com/ph-pka-ka-pkb-and-kb-explained-4027791
pdf for "keq expression calculator".(Page 1 of about 13 results)