Isolation of ammonia gas
Aislamiento del gas amoníaco
- Date
- 1756 · confidence medium
- Place
- Edinburgh, Scotland, United Kingdom
- Credited to
- Joseph Black (first isolation); independently re-isolated by Peter Woulfe, Carl Wilhelm Scheele and Joseph Priestley
- Field
- Matter & energy
⚠️ Disputed: the sources disagree.
What was discovered
Black first obtained gaseous ammonia by heating sal ammoniac with lime, though for over a century the gas was popularly credited above all to Priestley, who named it 'alkaline air' in 1773 and enabled its systematic study.
The gas was isolated several times independently: Black (1756, from sal ammoniac and calcined magnesia), Woulfe (1767), Scheele (1770) and Priestley (1773), who called it 'alkaline air' and is the name most associated with it. Black's work grew out of his Edinburgh thesis (1754) and was published in 1756.
What it led to
- Berthollet's determination of its composition in 1785
- Industrial use in refrigeration and as the basis of nitrogen fertilisers