If you know K_b for ammonia, NH₃, you can calculate the equilibrium constant K_a for the reaction NH₄⁺ NH₃ + H⁺
By which of the following equations?

Question

If you know K_b for ammonia, NH₃, you can calculate the equilibrium constant K_a for the reaction NH₄⁺ If you know Kb for ammonia, NH3, you can calculate the equilibrium constant Ka for the reaction NH4+ NH3 + H+ By which of the following equations? A) Ka = KwKb B) Ka = 1/Kb C) Ka = Kb/Kw D) Ka = Kw/Kb

If you know K<sub>b</sub> for ammonia, NH<sub>3</sub>, you can calculate the equilibrium constant K<sub>a</sub> for the reaction NH<sub>4</sub><sup>+</sup> NH<sub>3</sub> + H<sup>+</sup> By which of the following equations? A) K<sub>a </sub>= K<sub>w</sub>K<sub>b</sub> B) K<sub>a </sub>= 1/K<sub>b</sub> C) K<sub>a </sub>= K<sub>b</sub>/K<sub>w</sub> D) K<sub>a </sub>= K<sub>w</sub>/K<sub>b</sub>

NH₃ + H⁺
By which of the following equations?

Quizplus · Accepted Answer

The equilibrium constant expression for the given reaction can be written as follows: 
KS1U1B1aS1U1B0 = [NHS1U1B13S1U1B0][HS1U1P1+S1S1P0]/[NHS1U1B14S1U1B0S1U1P1+S1S1P0][HS1U1P1+S1S1P0]
Using the given value of KS1U1B1bS1U1B0, we can write the following expression:
KS1U1B1bS1U1B0 = [NHS1U1B13S1U1B0][HS1U1P1+S1S1P0]/[NHS1U1B14S1U1B0S1U1P1+S1S1P0][HS1U1P1+S1S1P0]
Taking the reciprocal:
1/KS1U1B1bS1U1B0 = [NHS1U1B14S1U1B0S1U1P1+S1S1P0][HS1U1P1+S1S1P0]/[NHS1U1B13S1U1B0][HS1U1P1+S1S1P0]
Canceling out the terms with HS1U1P1+S1S1P0 on both sides, we get:
1/KS1U1B1bS1U1B0 = [NHS1U1B14S1U1B0S1U1P1]/[NHS1U1B13S1U1B0]
Multiplying the above equation by [NHS1U1B13S1U1B0]/[NHS1U1B14S1U1B0S1U1P1], we get:
KS1U1B1aS1U1B0 = [NHS1U1B13S1U1B0]/[NHS1U1B14S1U1B0S1U1P1]
Using the given value of KS1U1B1wS1U1B0 as 10^-14, we can rewrite the above equation as:
KS1U1B1aS1U1B0 = [NHS1U1B13S1U1B0]/([NHS1U1B14S1U1B0S1U1P1][H+S1U1P0]) = KS1U1B1bS1U1B0/KS1U1B1wS1U1B0. 
Thus, the correct choice is D.

If You Know Kb for Ammonia, NH3, You Can Calculate

If You Know K_b for Ammonia, NH₃, You Can Calculate