What undesirable precipitates might contaminate the product if a)there is excess carbonate in the solution. b)the silver chloride decomposes during digestion

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1. The main reactant is Cl-. When reacted with Ag,
Ag+ + Cl- --> AgCl
Now, if CO₃²⁻ is present, it would also yield,
Ag⁺ + CO₃²⁻ --> Ag₂CO₃
It would yield silver carbonate, which is undersirable.

2. The decomposition undergoes through a process called photodecomposition. The reaction is

2 AgCl --> 2 Ag + Cl₂
The undesirable precipitate is Ag because it could co-precipitate with silver nitrate which should be avoided.

C) electrons encircling a nucleus with neutrons and protons