The Periodic Table: Metals, Nonmetals, and Metalloids

The Periodic Table Created in 1869 by both Mendeleev and Meyers Mendeleev periodic table more widely accepted Organized by Atomic mass Chemical properties 11/12/2018

The Periodic Table Organized in regular, repeating patterns known as periodicity Elements in the same column or row have similar properties or patterns 11/12/2018

The Periodic Table Group or Family Period A vertical column on the periodic table Similar chemical and physical properties Period A horizontal row on the periodic table Properties change progressively across 11/12/2018

Mendeleev’s Periodic Table 11/12/2018

Mendeleev’s Periodic Table Based upon the repeating patterns, Mendeleev left blank spaces on his periodic table These spaces were eventually filled in with undiscovered elements Discovered elements had similar properties compared to their group 11/12/2018

Organized in order of increasing atomic mass 11/12/2018

Mendeleev’s Periodic Table Flaws in this periodic table: As mass increased, the properties did not all line up Led to confusion of properties of known elements Was solved with the discovery of the atomic number 11/12/2018

Modern Periodic Table Organized by atomic number and properties This led to the “periodic law” which states: The properties of the elements are periodic functions of their atomic number 11/12/2018

Modern Periodic Table Developed by British scientist Henry Mosley Arranged by increasing atomic number Determined elements fell into columns with other elements with similar properties There were no exceptions found 11/12/2018

Modern Periodic Table 11/12/2018

Periodic Families There are 10 main families on the periodic table Metals Alkali metals Alkaline earth metals Transition metals Inner-transition metals 11/12/2018

Periodic Families There are 10 main families of the periodic table Other metals Metalloids Nonmetals Halogens Noble Gases 11/12/2018

Metals Located below the stair step line Form cations Solids Shiny metallic appearance Malleable Ductile Conductive High melting point and densities 11/12/2018

Metalloids Located on the stair step line Have properties of both metals and nonmetals Form both cations and anions Make good semiconductors Does NOT include aluminum (other metal) 11/12/2018

Nonmetals Located above the stair step line Form anions Solids, liquids and gases Poor conductors Brittle Not malleable or ductile 11/12/2018

Alkali Metals Located in Group 1 Low density 1 valence electron Forms a +1 cation Highly reactive in water 11/12/2018

Alkaline Earth Metals Located in Group 2 Harder and denser than alkali metals 2 valence electrons Forms a +2 cation Reducing agents (reactive) 11/12/2018

Transition Metals Located in the “d” block High densities and melting points White lustrous metals (except copper) Form cations 11/12/2018

Inner-transition Metals Located in “f” block Also known as the rare earth metals Most are synthetic (man made) Most are radioactive Form cations 11/12/2018

Other Metals Located next to the transitional metals and under the stair step line Properties vary Form cations 11/12/2018

Halogens Located in group 17 7 valance electrons Forms a -1 anion Highly electronegative Diatomic Very reactive with the alkali metals 11/12/2018

Noble Gases Located in group 18 8 valance electrons Do not react!!!! Also known as Inert Gases 11/12/2018