Crossword clues for periodic table
periodic table
Longman Dictionary of Contemporary English
Wiktionary
n. (context chemistry English) A tabular chart of the chemical elements according to their atomic numbers so that elements with similar properties are in the same column.
WordNet
n. a tabular arrangement of the chemical elements according to atomic number as based on the periodic law
Wikipedia
The periodic table is a tabular arrangement of the chemical elements, ordered by their atomic number (number of protons), electron configurations, and recurring chemical properties. This ordering shows periodic trends, such as elements with similar behavior in the same column. It also shows four rectangular blocks with some approximately similar chemical properties. In general, within one row (period) the elements are metals on the left, and non-metals on the right.
The rows of the table are called periods; the columns are called groups. Six groups (columns) have names as well as numbers: for example, group 17 elements are the halogens; and group 18, the noble gases. The periodic table can be used to derive relationships between the properties of the elements, and predict the properties of new elements yet to be discovered or synthesized. The periodic table provides a useful framework for analyzing chemical behavior, and is widely used in chemistry and other sciences.
Dmitri Mendeleev published in 1869 the first widely recognized periodic table. He developed his table to illustrate periodic trends in the properties of the then-known elements. Mendeleev also predicted some properties of then-unknown elements that would be expected to fill gaps in this table. Most of his predictions were proved correct when the elements in question were subsequently discovered. Mendeleev's periodic table has since been expanded and refined with the discovery or synthesis of further new elements and the development of new theoretical models to explain chemical behavior.
All elements from atomic numbers 1 ( hydrogen) to 118 ( ununoctium) have been discovered or synthesized, with the most recent additions (elements 113, 115, 117, and 118) being confirmed by the IUPAC on December 30, 2015. The first 94 elements exist naturally, although some are found only in trace amounts and were synthesized in laboratories before being found in nature. Elements with atomic numbers from 95 to 118 have only been synthesized in laboratories or nuclear reactors. Synthesis of elements having higher atomic numbers is being pursued. Numerous synthetic radionuclides of naturally occurring elements have also been produced in laboratories.
This page shows large-cell versions of the periodic table. For each element name, symbol, atomic number, and mean atomic mass value for the natural isotopic composition of each element are shown. The periodic table of the chemical elements is a tabular method of displaying the chemical elements.
The two layout forms originate from two graphic forms of presentation of the same periodic table. Historically, when the f-block was identified it was drawn below the existing table, with markings for its in-table location (this page uses dots or asterisks). Also, a common presentation is to put all 15 lanthanide and actinide columns below, while the f-block only has 14 columns. The fifteenth (rightmost) lanthanide and actinide are d-block elements, belonging to group 3, with scandium and yttrium.
Although precursors to this table exist, its invention is generally credited to Russian chemist Dmitri Mendeleev in 1869. Mendeleev invented the table to illustrate recurring ("periodic") trends in the properties of the elements. The layout of the table has been refined and extended over time, as new elements have been discovered, and new theoretical models have been developed to explain chemical behavior. __NOTOC__
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18-column layout
Periodic table with f-block separated|link=Periodic table (large cells)#18-column
Periodic table may refer to:
- The Periodic Table of chemical elements
- Periodic Table of Shapes, about mathematical shapes
It is also the title of books about the table:
- For the book by Primo Levi, see The Periodic Table (book).
- For the book by Simon Basher, see The Periodic Table (Simon Basher book).
For elements that are solid at standard temperature and pressure the table gives the crystalline structure of the most thermodynamically stable form(s) in those conditions. In all other cases the structure given is for the element at its melting point.
- Configurations of elements 103 and 104 are uncertain; those for elements 105 and above are not available. Predictions from reliable sources have been used for these elements.
- Grayed out electron numbers indicate subshells that are filled to their maximum.
- The bracketed noble gas symbols on the left represent the inner configurations that are the same in each period. Written out these are:
- Note the non-linear shell ordering, which comes about due to the different energies of smaller and larger shells.
Usage examples of "periodic table".
There was rote memorization about the Periodic Table of the Elements, levers and inclined planes, green plant photosynthesis, and the difference between anthracite and bituminous coal.
Assuming that the spell works, though, we can play Mendeleev and predict the properties of eka-lead by extrapolating from those in the 'lead' series in the periodic table (carbon, silicon, germanium, tin, lead).
For example, they draw us a periodic table of the elements, so they get to name all the chemical elements, the idea of aa atom, the idea of a nucleus, protons, neutrons, electrons.
For example, they draw us a periodic table of the elements, so they get to name all the chemical elements, the idea of a atom, the idea of a nucleus, protons, neutrons, electrons.
Hundreds of thousands of specialized selections of the library's contents were accessible in similar ways--and Yatima had climbed the Evolutionary Tree, hopscotched the Periodic Table, walked the avenue-like Timelines for the histories of fleshers, gleisners, and citizens.
It's almost like a periodic table with the top right-hand section chopped out—.
That's about all there is to a periodic table, to oversimplify it.
It has a name and a place on the periodic table (next door to Marie Curie’.
It illuminated the cause of that stellar engine's wreck, and revealed a new geometry of the universe, and showed him a deeper meaning even in the familiar pattern of the periodic table of the elements.