Types of Chemical Reactions Taking Place in Solvents:
- Acid-base reactions
- Precipitation reactions
- Amphoteric reactions
- Salt formation reactions
- Solvolysis reactions
- Solvation reactions
- Redox reactions
Acid-base reactions: Acid-base reactions are chemical reactions that occur between an acid and a base, resulting in the formation of a salt and a solvent
Self-Ionization of Solvents
We have already said that ionic solvents are polar compounds and undergo self-ionization. Self-ionization of some important solvents is given below:
| Solvent | Solvent Cation (Acid Ion) |
Solvent Anion (Base Ion) |
|---|---|---|
| 2H2O ⇌ | H3O+ | OH− |
| 2NH3 ⇌ | NH4+ | NH2− |
| 2BrF3 ⇌ | BrF2+ | BrF4− |
| 2HgBr2 ⇌ | HgBr+ | HgBr3− |
| 2SO2 ⇌ | SO2+ | SO32− |
| 2H2SO4 ⇌ | H3SO4+ | HSO4− |
| CH3COOH ⇌ | CH3COOH2+ | CH3COO− |
| 2HClO4 ⇌ | H2ClO4+ | ClO4− |
| 3HF ⇌ | H2F+ | HF2− |
| N2O4 ⇌ | NO+ | NO3− |
Acid-Base Reactions in Different Solvents
An acid-base reaction in a non-aqueous solvent can be explained on the basis of the solvent system concept of acids and bases. According to this concept:
- Acid: A substance that gives the solvent cation.
- Base: A substance that gives the solvent anion.
Example in liquid ammonia:
NH4Cl (acid) + KNH2 (base) ⇌ KCl (salt) + 2NH3 (solvent)
NH4Cl (acid) + 2Na ⇌ NaCl (salt) + 2NH3 (solvent)+ H2
Mg2Si + 4NH4Br (liq. NH3) → SiH4 ↑ + 2MgBr2 + 4NH3
Mg2Ge + 4NH4Br (liq. NH3) → GeH4 ↑ + 2MgBr2 + 4NH3
Na3As + 3NH4Br (liq. NH3) → AsH3 ↑ + 3NaBr + 3NH4+
Chemical Reactions of Ammono Bases in Liquid Ammonia
1. Acetamide and Potassium Amide
CH3CONH2 + KNH2 → CH3CONHK + NH3
2. Sulfamic Acid and Potassium Amide
H2NSO3H + 2 KNH2 → KNHSO2OK + 2 NH3
3. Acetylene and Potassium Amide
HC≡CH + KNH2 → H–C≡C–K + 2 NH3
4) Reaction with AgNO3
AgNO3 + KNH2 → AgNH2↓+ KNO₃
Observation: White precipitate of silver amide (AgNH2).
5) Reaction with PbI2
PbI2 + 2KNH2 → PbNH ↓+2KI + NH₃
Observation: Precipitate of lead(II) imide.
6) Reaction with HgI2
3HgI₂ + 6KNH₂ → Hg3(N2)↓ + 6KI + 4NH₃
Observation: White precipitate of mercury(II) nitride.
7) Reaction with BiI3
BiI3 + 3KNH2 → BiN ↓ + 3KI + 2NH₃
Observation: Precipitate of bismuth(III) nitride.