You are farming and loving life. You love the smell of ammonia and apply it to your field as a fertilizer. However, you have a pond which you use to water your crops and for your llamas drinking water. The ammonia you spread on your field washes into the pond (it has a volume of 3.0 x 10^6 L of water). When you test the pond water is has a pH of 9.81. How much liquid ammonia from your fertilizing made its way into the pond? Give your answer in L of ammonia.

Question

You are farming and loving life. You love the smell of ammonia and apply it to your field as a fertilizer. However, you have a pond which you use to water your crops and for your llamas drinking water. The ammonia you spread on your field washes into the pond (it has a volume of 3.0 x 10^6 L of water). When you test the pond water is has a pH of 9.81. How much liquid ammonia from your fertilizing made its way into the pond? Give your answer in L of ammonia.
Given: Kb(NH3) = 1.8 x 10^-5; the density of liquid ammonia is 0.771 g/cm^3

DrBob222 · Answer

NH3 + HOH ==> NH4^+ + OH^-
Kb = (NH4^+)(OH^-)/(NH3)
Convert pH to OH^-, substitute into Kb and solve for NH3 (in mols/L).
Convert to mols (M x L), convert that to grams NH3 and from there use density and solve for cc and convert to L. Post your work if you get stuck.