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Bell Work. Compare and contrast groups, families, and periods?. Physical Science – Lecture 59 . Periodic Table Specific Metals. Classifying Elements . Elements are classified according to their properties. The major categories of elements are the metals, nonmetals, and metalloids. . METALS.
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Bell Work • Compare and contrast groups, families, and periods?
Physical Science – Lecture 59 Periodic Table Specific Metals
Classifying Elements • Elements are classified according to their properties. The major categories of elements are the metals, nonmetals, and metalloids.
METALS • Almost 75% of all elements are classified as metals.
They are not all like silver (Ag), gold (Au), or platinum (Pt). • Those are the very cool and shiny ones. There are other metals like potassium (K) and iridium (Ir) that you might not think about right away.
Which ones are metals? • There are four traits to help identify if an element is a metal or not.
Trait 1 - Conduction • Metals are good at conducting electricity.
Trait 2 - Reactivity • Metals are very reactive, some more than others, but most form compounds with other elements quite easily.
Trait 3 - Cations • Metals usually make positive ions when the compounds are dissolved in solution.
Trait 4 - Alloys • Metals are easily combined. • Mixtures of many elements are called alloys.
Metals - Location • Metals are located on the left side and the middle of the periodic table. • Group 1A and Group 2A are the most active metals. • The transition elements, groups 1B to 8B, are also considered metals.
Properties • Metals are shiny solids are room temperature (except mercury), with characteristic high melting points and densities.
Properties • Metals can be deformed without breaking. • Malleability is the ability of a metal to be hammered into shapes. • Ductility is the ability of a metal to be drawn into wire.
Properties • Because the valence electrons can move freely, metals are good heat conductors and electrical conductors.
Transition Metals • Transition metals can put up to 32 electrons in their second to last shell.
Bonding • Transition metals can use the two outermost shells/orbitals to bond with other elements. • This allows them to bond with many elements in a variety of shapes.
Properties of Transition Metals • These elements are very hard, with high melting points and boiling points.
ALKALI METALS • The far left column is Group One (Group I).
Who's not in the family? • Hydrogen is a very special element of the periodic table and doesn't belong to any family.
Alkali Metal Common Properties • Lower densities than other metals • One loosely bound valence electron • Largest atomic radii in their periods • Low ionization energies • Low electronegativities • Highly reactive • From +1 Cations
Alkaline Earth Metals • Group 2.
Alkali Earth’s Common Properties • Two electrons in the outer shell • Low electron affinities • Low electronegativities • Readily form divalent cations. • Smaller than alkali metals.
Rare-Earth Elements • The two rows at the bottom of the table • Also called inner-transition elements.
Lanthanide Series • The top row of rare-earth elements
Lanthanide’s Common Traits • Silvery metals that tarnish easily. • Relatively soft metals • High melting and boiling points. • React to form many different compounds. • Used in lamps, magnets, lasers, and to improve the properties of other metals • Can be found naturally on Earth. • Only one element is radioactive.
The Actinide Series • The bottom row of rare-earth elements
Actinide’s Common Traits • All radioactive • Some are not found in nature. • Some have only been made in labs. • Used in medicine and nuclear devices