Answer:
C. Precipitation of white bismuth hydroxide.
Explanation:
When aqueous ammonia is added to a solution that has Bi3+ and CU2+ cations, what we would have as a chemical result is the precipitation of white Bismuth hydroxide.
The chemical reaction for this can be written as,
Bi3+ + 2NH3 + 3H2O ⇌ Bi(OH)3(s) + 3NH4
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