About: http://webisa.webdatacommons.org/20293978

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	A chemical substance is a kind of matter with a definite composition and set of properties.[33] Strictly speaking, a mixture of compounds, elements or compounds and elements is not a chemical substance, but it may be called a chemical.
http://www.w3.org/ns/prov#wasQuotedFrom	docstoc.com