Assertion: ammonia | /r/HasProperty | refrigerated
Facets:
value: because of its relatively high boiling point
type: CAUSE
value: potentially
type: DEGREE
value: compared to helium
type: OTHER
Source sentences:
text: Because of its relatively high boiling point (compared to helium and hydrogen), ammonia could potentially be refrigerated and liquefied aboard an airship to reduce lift and add ballast (and returned to a gas to add lift and reduce ballast).