Layout and structure of the Periodic Table
The modern periodic table arranges elements in increasing atomic number, in rows. Each element may be shown with an element symbol, atomic number, element name, and average atomic mass.
Periods and Groups
Rows in the periodic table are called periods. There are 7 periods, numbered 1 to 7 starting at the top. Columns are called groups or families. There are 18 groups, numbered 1 to 18 starting at the left. The periodic table above shows the numbering of each period and group. The period represents the number of shells an element has, and the group represents how many valence electrons the element has.
Special Blocks and Group Names
Groups can have special names. As shown in the periodic table above, Group 1 are the alkali metals (with the exception of hydrogen), Group 2 alkaline earth metals, Group 3 to 12 transition metals, Group 17 halogens, and Group 18 noble gases. The elements colored yellow are other metals, the green are metalloids, and the purple are non-metals. The two separate horizontal rows on the bottom are lanthanoids on the top and actinoids on the bottom.
Rows in the periodic table are called periods. There are 7 periods, numbered 1 to 7 starting at the top. Columns are called groups or families. There are 18 groups, numbered 1 to 18 starting at the left. The periodic table above shows the numbering of each period and group. The period represents the number of shells an element has, and the group represents how many valence electrons the element has.
Special Blocks and Group Names
Groups can have special names. As shown in the periodic table above, Group 1 are the alkali metals (with the exception of hydrogen), Group 2 alkaline earth metals, Group 3 to 12 transition metals, Group 17 halogens, and Group 18 noble gases. The elements colored yellow are other metals, the green are metalloids, and the purple are non-metals. The two separate horizontal rows on the bottom are lanthanoids on the top and actinoids on the bottom.
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The periodic table can be split into special blocks as well. It can be split into s,p,d, and f orbitals as well as the energy levels. Each row is the energy level in numerical values of 1 to 7. For example Nitrogen's electron configuration is 1s2s2p3, and Oxygen's is 1s2s2p4. So as you move left to right in the same block, you increase the number of electrons in the final orbital.
Electron Configuration
From knowing the electron configuration of an element, we can know its physical and chemical properties, and its number of valence electrons. An electron configuration is unique to one element and to that particular position on the periodic table.
Electron Configuration
From knowing the electron configuration of an element, we can know its physical and chemical properties, and its number of valence electrons. An electron configuration is unique to one element and to that particular position on the periodic table.
http://www.webelements.com/nexus/content/periodic-table-groupshttp://chemwiki.ucdavis.edu/Inorganic_Chemistry/Electronic_Configurations