About: http://webisa.webdatacommons.org/83056700

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	Substances that are gases, such as air and carbon dioxide, have an index of refraction,<math>n</math>, of about 1.
http://www.w3.org/ns/prov#wasQuotedFrom	mathforum.org