sulphite

A chemist adds sodium sulphite to a clear solution in a laboratory.

Definition

1. Noun:
   • Chemical compound: "sulphite" (also spelled "sulfite" in American English) is a salt or ester of sulphurous acid, containing the anion SO₃²⁻. It is commonly used as a preservative in food and beverages, and in industrial processes such as paper production.
   • Specific substance: In chemistry, "sulphite" refers to any compound formed by replacing one or both hydrogen atoms of sulphurous acid with a metal or organic group.

Usage Examples

• Noun:
  • Sodium sulphite is often added to wine to prevent oxidation. (A preservative used in winemaking.)
  • The laboratory tested the sample for the presence of sulphite. (The chemical compound was analysed.)
  • Some people are allergic to sulphite in dried fruits. (A preservative that can cause adverse reactions.)

Advanced Usage

• "sulphite pulp": a type of wood pulp produced using sulphite-based chemicals in paper manufacturing.

  • The mill specializes in producing sulphite pulp for high-quality paper. (Pulp made with sulphurous acid derivatives.)

• "sulphite sensitivity": an adverse reaction to sulphite compounds, often causing asthma-like symptoms.

  • Patients with sulphite sensitivity should avoid processed foods labelled with preservatives. (A medical condition triggered by sulphite ingestion.)

Variants and Related Words

• Sulphite (n, British spelling): the standard spelling in British English.
• Sulfite (n, American spelling): the preferred spelling in American English.
  • The chemical formula for sulfite is SO₃²⁻. (Same compound, different spelling.)
• Sulphurous (adj): relating to or containing sulphur.
  • Sulphurous acid is the parent compound of sulphites. (The acid from which sulphites derive.)
• Sulphate (n): a different compound containing the SO₄²⁻ ion.
  • Do not confuse sulphite with sulphate; they have different chemical properties. (Related but distinct substances.)

Synonyms

• Preservative: a substance added to food to prevent spoilage (when referring to its common use).
  • Many packaged foods rely on sulphite as a preservative. (A synonym for its function, not a direct chemical synonym.)
• Salt of sulphurous acid: a technical description of the compound.
  • Sodium sulphite is a typical salt of sulphurous acid. (A more formal synonym.)

Related Idioms

• "A sulphite-free diet": a dietary restriction avoiding foods containing sulphite preservatives.
  • After her diagnosis, she adopted a strict sulphite-free diet. (A diet without sulphite-containing foods.)