Definition
Sodium hypobromite is an inorganic compound with the chemical formula NaOBr. It is the sodium salt of hypobromous acid (HOBr) and functions as an oxidizing agent and disinfectant.
Overview
Sodium hypobromite is typically obtained as an aqueous solution, often generated in situ by the reaction of bromine with sodium hydroxide. It is employed in various industrial and laboratory applications, including bleaching, water treatment, and organic synthesis where it serves as a source of bromine in electrophilic bromination reactions. Compared to its chlorine analogue, sodium hypochlorite, sodium hypobromite is less stable and more reactive toward organic substrates.
Etymology/Origin
The name derives from “sodium” (the alkali metal Na⁺), “hypo‑” indicating the hypohalite anion (OBr⁻) derived from hypobromous acid, and the suffix “‑ite” which denotes a lower oxidation state oxyanion. The term follows standard IUPAC nomenclature for hypohalite salts.
Characteristics
| Property | Description |
|---|---|
| Chemical formula | NaOBr |
| Molar mass | 106.90 g·mol⁻¹ |
| Appearance | Colorless to pale yellow aqueous solution; solid form (when isolated) is a white crystalline powder that decomposes rapidly. |
| Solubility | Highly soluble in water; the solution is typically prepared at concentrations up to 10 % w/w. |
| Stability | Unstable in dry form; decomposes on heating or exposure to light, yielding sodium bromide (NaBr) and oxygen or bromine. |
| Acid–base behavior | Acts as a weak base in aqueous solution, forming hypobromous acid (HOBr) upon protonation. |
| Oxidizing power | Possesses a standard reduction potential of +1.57 V for the BrO⁻/Br⁻ couple, making it a strong oxidizer. |
| Safety | Irritant to skin, eyes, and respiratory tract; can release toxic bromine vapors upon decomposition. Proper handling requires protective equipment and ventilation. |
Related Topics
- Hypobromous acid (HOBr) – the parent acid of the hypobromite ion.
- Sodium hypochlorite (NaOCl) – a chemically analogous chlorine-based bleaching agent.
- Bromine chemistry – broader context of bromine’s oxidation states and compounds.
- Oxidizing agents – class of chemicals that accept electrons in redox reactions.
- Disinfection and water treatment – applications where sodium hypobromite may be employed.