Definition

Noun: 1. A white, crystalline salt: Ammonium carbonate is a chemical compound with the formula (NH₄)₂CO₃. It is a carbonate salt of ammonia and ammonium ions. 2. A source of ammonia gas: It readily decomposes to release ammonia, carbon dioxide, and water vapor, which is the basis for its historical and industrial uses.

Usage and Examples

• In manufacturing: Ammonium carbonate is used in the manufacture of smelling salts and baking powder.
• As a chemical reagent: It is used in the production of other ammonium compounds.

Advanced Usage

• "Baker's ammonia": A common name for ammonium carbonate when used as a leavening agent in baking, particularly in older recipes or for specific crisp cookies.

Variants and Related Words

• Ammonium bicarbonate (NH₄HCO₃): A related compound also used as a leavening agent, which decomposes at a lower temperature.
• Ammonium carbamate (NH₂COONH₄): Another related salt often present in commercial "ammonium carbonate," which is actually a mixture of ammonium bicarbonate and ammonium carbamate.

Synonyms

• Baker's ammonia (when referring to its use in baking)
• Hartshorn (an archaic name, derived from the historical source of the compound from deer antlers)
• Sal volatile (a historical term often referring to smelling salts made from ammonium carbonate)

Notes on Different Meanings

The term "ammonium carbonate" primarily refers to the specific chemical compound. Its meaning is tied directly to its chemical composition and its functional uses (e.g., leavening, source of ammonia). It does not have idiomatic or phrasal verb uses.

Noun

1. a carbonate of ammonium; used in the manufacture of smelling salts and baking powder and ammonium compounds