Nickel Hydroxide Precipitation
NiCl2 + 2NaOH → Ni(OH)2↓ + 2NaCl
Overview
Nickel chloride reacts with sodium hydroxide to form a green precipitate of nickel(II) hydroxide (Ksp = 5.5 × 10⁻¹⁶). The apple-green precipitate does not dissolve in excess NaOH (not amphoteric) but dissolves in ammonia to form the deep blue hexaammine nickel(II) complex.
Participants
| Role | Substance | Coefficient | State |
|---|---|---|---|
| Reactant | Sodium Hydroxide NaOH | 2 | (aq) |
| Product | Sodium Chloride NaCl | 2 | (aq) |
Everyday Example
Nickel hydroxide is the active material in rechargeable nickel-metal hydride (NiMH) batteries used in hybrid cars and consumer electronics.
Industrial Importance
Nickel hydroxide is a critical battery material for NiCd and NiMH batteries, and is also used in nickel plating and as a catalyst precursor.
Properties
- Type
- Precipitation
- Reversible
- No
- Energy
- Exothermic
- ΔH
- -55.0 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 Nickel Hydroxide Precipitation?
The balanced equation is: NiCl₂ + 2NaOH → Ni(OH)₂↓ + 2NaCl.
What type of reaction is Nickel Hydroxide Precipitation?
Nickel Hydroxide Precipitation is a precipitation reaction.
Is Nickel Hydroxide Precipitation exothermic or endothermic?
Nickel Hydroxide Precipitation is exothermic (releases energy). The enthalpy change (ΔH) is -55.0 kJ/mol.