Hydrogen chloride Strong acid in aqueous (HCl); gas in pure form 🏗️ Materials PDB source ↓ Drag to rotate · scroll to zoom 3D viewer requires JavaScript. Static renders available below. Structure Formula HCl Molecular weight 36.458 g/mol Heavy atoms 1 Total atoms 2 Composition H ×1 Cl ×1 SMILES Cl ⧉ Copy Class Inorganic