Question

I attempted to answer some of this question, but don't think I'm understanding what's needed. Chem makes my eyes cross... Liquid ammonia, NH3(l), is an ionizing solvent like water. This means that NH3(l) can dissolve many different ionic compounds and can undergo autoionization. Therefore, there can be acidic, neutral, or basic species in solutions of liquid ammonia.

(a) (Write the chemical equation, using the Brønsted-Lowry perspective, that describes the autoionization of NH3(l).

--NH3 --> NH2 + H- ??

(b) Identify the species in pure NH3(l) that can act as Brønsted acids and as Brønsted bases. (There are more than one for each case.)

--??

(c) Write the mass-action expression for the autoionization constant of liquid ammonia.

ka = ([M product (?)][M of other product (?)]/[M NH3] ...?

(d) At -50°C, the autoionization constant of ammonia is 10^-30. What are the conditions for “neutral”, “acidic”, and “basic” liquid ammonia solutions at -50°C?

--neutral kb=ka; acidic ka>kb; basic ka

(e) Identify two different compounds so that, when each is dissolved in liquid ammonia, one gives rise to an "acidic" solution and the other to a "basic" solution. Write out the chemical equilibrium that shows how one behaves as an acid, and the other behaves as a base in NH3(l).

--NaCl? NaOH?

Answer 1