Assertion: phosphine | /r/HasProperty | described by philippe gengembre
Facets:
value: chemically
type: MANNER
value: as a product
type: OTHER
value: in 1783
type: TEMPORAL
Source sentences:
text: Phosphine has had a nearly 100-year of history of use as a fumigant after it was first described chemically by Philippe Gengembre in 1783 as a product of heating elemental phosphorus in a solution of potassium carbonate (40).