Compound reference
Hydrogen chloride
HCl
The chemistry
One polar bond. Cl pulls the electrons; H is left a little positive. Drop it in water and you get stomach acid.
Remember it as…
H δ+ - Cl δ−. The arrow points to chlorine. In water it dissociates: HCl → H⁺ + Cl⁻.
Common mix-up
A POLAR covalent bond is not the same as an IONIC one. HCl shares electrons unevenly (polar covalent); NaCl transfers them outright (ionic). The electronegativity gap of HCl (~1.0) sits firmly in polar-covalent territory.
Where the name comes from
Chlorine from Greek chloros (pale green) - for the gas's color. Hydrochloric acid is "muriatic acid" historically, from Latin muria (brine).
Where you meet it
Stomach pH 1–2 thanks to dissolved HCl; pickling acid; pool-water disinfectant; aggressive enough to dissolve most metals to chlorides + H₂.
PubChem facts
- IUPAC name
- chlorane
- Molecular weight
- 36.46 g/mol
Also known as: hydrochloric acid (the water solution), muriatic acid
Handling note
A corrosive gas that forms hydrochloric acid in water; irritating and toxic to breathe.
Acids and basesBondingMolecular geometry
Chemical data from PubChem (NIH/NCBI)