If you know Kb for ammonia, NH3, you can calculate the equilibrium constant, Ka, for the following reaction: NH4+ NH3 + H+ by the equation: Ka = 1 / Kb Ka = Kb / Kw Ka = Kw / Kb Ka = Kw × Kb None of these choices are correct.

Ka = Kw / Kb

Explanation:

Hello,

By means of all dissociations, considering the relationship between Ka (acid dissociation constant), Kb (basic dissociation constant) and Kw (water's dissociation constant) a feasible way to obtain Ka in terms of Kb is:

Whereas Kw is always equal to 1x10⁻¹⁴, the answer is: Ka = Kw / Kb.

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