Yes, in chemistry a pure substance means either an element or a compound. Thus, hydrogen, oxygen, sodium, iron, copper etc. are pure substances; and so are compounds such as water, sugar, ammonia, sodium chloride, methane, ethanol etc. A compound is composed of two or more elements combined in a fixed ratio by mass. Like an element, a compound also has a distinct chemical identity. A mixture is not a pure substance as it is a collection of two or more elements/compounds in varying ratio. Air, sea water, gasoline, vegetable oils, steel etc. are mixtures.
Hudson (CDP), Massachusetts. Hudson is a census-designated place (CDP) in the town of Hudson in Middlesex County, Massachusetts, United States. The population was 14,907 at the 2010 census.
2 Square Miles of City. Hudson, New York, is located on the east side of the Hudson River in Columbia County, 120 miles north of New York City, 45 miles south of Albany and 160 miles west of Boston. The city is surrounded by the town of Greenport to the north, east and south, and by the Hudson River to the west.