halogen: Quick Facts

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Facts

Also Known As	halogen element • Group 17 element • Group VIIa element

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A color-coded periodic table of the elements displays each element's symbol and atomic number, with categories such as alkali metals, noble gases, halogens, transition metals, and actinoid elements distinguished by different background colors.

Diagram showing the formation of an ionic bond between sodium (Na) and chlorine (Cl) atoms. Sodium loses an electron to become Na+, chlorine gains an electron to become Cl-, resulting in sodium chloride (NaCl), or table salt.

Bohr model diagram of a chlorine atom showing a central nucleus with red and yellow spheres for protons and neutrons, surrounded by three electron orbits with blue electrons.

Understanding the Organization of the Periodic Table

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Topics

organohalogen compound iodine fluorine chlorine bromine astatine tennessine molecular lattice halogenation chemical element rare-earth element transition metal hydrogen alkali metal actinoid element alkaline-earth metal carbon group element boron group element oxygen group element nitrogen group element

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chemical industry: Halogens and their compounds

Key People

ean-Baptiste-André Dumas

Jean-Baptiste-André Dumas

French chemist

Periodic Table of the elements concept image (chemistry)

Facts You Should Know: The Periodic Table Quiz

Periodic table of the elements. Left column indicates the subshells that are being filled as atomic number Z increases. The body of the table shows element symbols and Z. analysis and measurement

Periodic Table of the Elements