What is the actual concentration of molecular NH₃ in a 0.200 M solution of ammonia? (K_b value for ammonia = 1.80 *10^-5)

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Quizplus · Accepted Answer

The actual concentration of molecular ammonia in a solution can be calculated using the equilibrium constant (Kb) for ammonia and the initial concentration. Given that the Kb value for ammonia is $1.8 \times 10^{-5}$, we can use the formula for the base ionization equilibrium to find the concentration of NH3 that does not ionize. The calculation involves setting up an equilibrium expression and solving for the concentration of NH3 that remains unreacted. The slight difference between the initial concentration (0.200 M) and the concentration of NH3 that remains (0.198 M) accounts for the small amount that ionizes, according to the Kb value. This calculation assumes that the ionization of NH3 in water is a minor extent, which is why the concentration of molecular NH3 remains close to the initial concentration.

What Is the Actual Concentration of Molecular NH3 in a 0.200

What Is the Actual Concentration of Molecular NH₃ in a 0.200