Periodic Table of Elements

02/05/09

Cl

Chlorine

Atomic Number

17

Atomic Symbol

Cl

	Name	Chlorine
	Meaning	Named for the Greek word 'chlooros' meaning 'pale green'

Group

Halogens

Atomic Weight

35.453

Density, g/cubic cm at STP

0.003214

Melting Point, °C

-100.84

Boiling Point, °C, 1 atm

-34

Naturally Occurring Isotopes

Cl-35, Cl-37

Discoverer

Scheele

Year

1774

Ionization Energy, eV

12.9676

Configuration

[Ne] 3s2 3p5

Description

Pale green gas at STP with a choking odor

References: Holden, Norman E. (March 30, 2004). "History of the origin of the chemical elements and their discoverers." National Nuclear Data Center. Retrieved October 7, 2005 from http://www.nndc.bnl.gov/content/elements.html "List of elements by boiling point." (September 22, 2005). Wikipedia. Retrieved October 9, 2005 from http://en.wikipedia.org/wiki/List_of_elements_by_boiling_point "List of elements by density." (September 22, 2005). Wikipedia. Retrieved October 9, 2005 from http://en.wikipedia.org/wiki/List_of_elements_by_density "List of elements by melting point." (September 22, 2005). Wikipedia. Retrieved October 9, 2005 from http://en.wikipedia.org/wiki/List_of_elements_by_melting_point "NIST chemistry webBook." (2005). National Institute of Standards and Technology. Retrieved October 6, 2005 from http://webbook.nist.gov/chemistry/ Zucker, M.A.; Kishore, A. R.; Sukumar, R.; and Dragoset, R. A. (July 2005). "Elemental data index."  National Institute of Standards and Technology. Retrieved October 7, 2005 from http://physics.nist.gov/PhysRefData/Elements/cover.html