Ammonium vs ammonia
NH₄⁺ and NH₃ differ by one proton and one charge unit.
Ammonium has four N–H bonds; ammonia has three N–H bonds plus a lone pair.
Ionic solid · ammonium salt
Ammonium chloride
NH₄Cl
Ammonium chloride is NH₄Cl, an ionic solid composed of NH₄⁺ and Cl⁻ ions. The ammonium ion is a tetrahedral covalent polyatomic cation embedded in an ionic crystal.
Name distinction: ammonium chloride contains the ammonium ion NH₄⁺; it is not the same compound as ammonia NH₃.
Essentials
NH₄Cl is one NH₄⁺ ion for one Cl⁻ ion.
A +1 ammonium ion and a −1 chloride ion balance in a 1:1 formula unit.
Detail
The ammonium ion is tetrahedral.
Four hydrogen atoms occupy tetrahedral directions around nitrogen. Protonating ammonia uses its lone pair to form the fourth N–H bond.
Chloride
Cl⁻ is monatomic and does not have an internal bond framework.
Its role in the simple formula is charge balance and ionic interaction with ammonium.
Understand
Aqueous ammonium chloride can be mildly acidic because NH₄⁺ is a weak acid.
The ammonium ion can donate a proton to water, forming NH₃ and H₃O⁺ in an equilibrium. Chloride is a very weak Brønsted base in water.
Conjugate pair
NH₄⁺ / NH₃ is an acid–base pair.
Recognizing that pair links this page directly to the ammonia master.
Reference identifiers
Names and identifiers that pin down the chemical identity.
| Formula | NH₄Cl |
|---|---|
| CAS Registry Number | 12125-02-9 |
| Ions | NH₄⁺ and Cl⁻ |
Advanced
Push past the first model without losing the simple picture.
Is ammonium chloride molecular?
No. The solid is ionic, although NH₄⁺ itself contains covalent N–H bonds.
Why is NH₄⁺ tetrahedral?
Four bonding directions surround nitrogen after ammonia is protonated.
Why can an ammonium-chloride solution be acidic?
NH₄⁺ can donate a proton to water, while chloride contributes little basicity.
Constituent elements