Silver Chloride Precipitation
AgNO3 + NaCl → AgCl↓ + NaNO3
Overview
Silver nitrate reacts with sodium chloride to form a white curdy precipitate of silver chloride. AgCl has a very low Ksp of 1.8 × 10⁻¹⁰, making it essentially insoluble. The precipitate turns purple in light due to photodecomposition of AgCl to silver metal and chlorine. This is the basis of the chloride ion test.
Participants
| Role | Substance | Coefficient | State |
|---|---|---|---|
| Reactant | Silver Nitrate AgNO₃ | 1 | (aq) |
| Reactant | Sodium Chloride NaCl | 1 | (aq) |
| Product | Silver Chloride AgCl | 1 | (s) |
| Product | Sodium Nitrate NaNO₃ | 1 | (aq) |
Everyday Example
The silver chloride test for chloride ions in water is one of the first qualitative analysis tests taught in chemistry courses.
Industrial Importance
AgCl precipitation is used in water quality testing, photography (historical), and in the preparation of silver chloride electrodes for electrochemistry.
Properties
- Type
- Precipitation
- Reversible
- No
- Energy
- Exothermic
- ΔH
- -65.5 kJ/mol
Related Reactions
Aluminum Hydroxide Precipitation
Barium Carbonate Precipitation
Barium Sulfate Precipitation
Cadmium Sulfide Precipitation (Yellow)
Calcium Carbonate Precipitation
Calcium Fluoride Precipitation (Fluorite)
Calcium Oxalate Precipitation (Kidney Stones)
Calcium Phosphate Precipitation (Bone Mineral)
Calcium Sulfate Precipitation (Gypsum)
Chromium(III) Hydroxide Precipitation
Frequently Asked Questions
What is the equation for Silver Chloride Precipitation?
The balanced equation is: AgNO₃ + NaCl → AgCl↓ + NaNO₃.
What type of reaction is Silver Chloride Precipitation?
Silver Chloride Precipitation is a precipitation reaction.
Is Silver Chloride Precipitation exothermic or endothermic?
Silver Chloride Precipitation is exothermic (releases energy). The enthalpy change (ΔH) is -65.5 kJ/mol.