p-block
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Template:Periodic table (p-block)
The p-block of the periodic table of the elements consists of the last six groups except helium (which is located in the s-block). In the elemental form of the p-block elements, the highest energy electron occupies a p-orbital. The p-block contains all of the nonmetals (except for hydrogen and helium, which are in the s-block) and semimetals, as well as the poor metals.[not verified in body]
The groups of the p-block are:[not verified in body]
- 13 (IIIB, IIIA): Boron group
- 14 (IVB, IVA): Carbon group
- 15 (VB, VA): Nitrogen group (or pnictogens)
- 16 (VIB, VIA): Chalcogens
- 17 (VIIB, VIIA): Halogens
- 18 (0, VIIIA): Noble gases (excluding helium)
History
Many of the p-block elements have been known since antiquity, and all naturally occurring p-block elements with the exception of astatine were discovered[by whom?] before 1900.[1] Astatine was finally discovered in 1940 by Dale R. Corson, Kenneth Ross MacKenzie, and Emilio Segrè at the University of California, Berkeley.
The remaining p-block elements are hypothesized, based on periodic trends, to be elements 113–118, although it is currently unknown if they are actually p-block elements.[citation needed]
Properties
The p-block is one of two blocks in the periodic table to contain nonmetals (although the s-block only contains two nonmetals, hydrogen and helium). As such, it has some of the most diverse properties of any region in the periodic table. The metals in this region of the periodic table are, in general, softer and have lower melting points than transition metals. The p-block is the only region of the periodic table to contain metalloids. In general, the farther one goes to the right, and the farther one goes up in the p-block, the less metallic the elements get; the metalloids form a diagonal line from the upper left to the lower right of the p-block.
All elements in the p-block have their outermost electron in a p-subshell.[citation needed]
Template:Periodic table (p-block trend)
References
- ^ "International Union of Pure and Applied Chemistry > Periodic Table of the Elements". Old.iupac.org. Retrieved 2012-08-13.
