What are the example of substitution reactions?

1. Halogenation: In this reaction, a hydrogen atom in a hydrocarbon molecule is replaced by a halogen atom (e.g. chlorine, bromine, or iodine).

2. Nucleophilic substitution: In this reaction, a nucleophile attacks an electrophilic center in a molecule, resulting in the substitution of one group with another.

3. Electrophilic aromatic substitution: In this reaction, an electrophile attacks an aromatic ring, resulting in the substitution of one group with another.

4. Radical substitution: In this reaction, a radical species replaces a hydrogen atom in a molecule, resulting in the substitution of one group with another.

5. Metal-catalyzed substitution: In this reaction, a metal catalyst facilitates the substitution of one group with another in a molecule.

Single Displacement Reactions

- Metal + Acid → Salt + Hydrogen gas
- Example: Iron + Hydrochloric acid → Iron(II) chloride + Hydrogen gas (Fe + 2HCl → FeCl₂ + H₂)
- Metal + Non-metal → Ionic compound
- Example: Sodium + Chlorine → Sodium chloride (Na + Cl₂ → 2NaCl)

Double Displacement Reactions

- Salt + Salt → New salt + New salt
- Example: Silver nitrate + Sodium chloride → Silver chloride + Sodium nitrate (AgNO₃ + NaCl → AgCl + NaNO₃)
- Base + Acid → Salt + Water
- Example: Sodium hydroxide + Hydrochloric acid → Sodium chloride + Water (NaOH + HCl → NaCl + H₂O)

Other Substitution Reactions

- Nucleophilic Substitution Reactions:
- Example: Hydroxide ion + Alkyl halide → Alcohol + Halide ion (OH⁻ + R-X → R-OH + X⁻)
- Electrophilic Substitution Reactions:
- Example: Electrophile + Aromatic compound → Substituted aromatic compound (E⁺ + Ar-H → Ar-E + H⁺)
- Radical Substitution Reactions:
- Example: Radical + Alkane → Substituted alkane + Radical (R• + RH → R-R + H•)