Periodic Table and Valence Electrons

Flashcards covering key vocabulary related to the periodic table, types of elements, and valence electrons.

Metals

An element that is generally shiny (luster), is easily pulled into wires (ductility) or hammered into thin sheets (malleability), and is a good conductor of electricity and thermal energy.

Metallic Properties (Right to Left Trend)

Tend to increase from right to left across the periodic table.

Metallic Properties (Top to Bottom Trend)

From the top of a group of elements to the bottom, the metallic properties tend to increase.

Group 1

Alkali Metals.

Alkali Metals

Very reactive elements, pure alkali metals are silver in color, very soft, and have very low density. Examples include Lithium, Sodium, Potassium, Rubidium, Cesium, and Francium.

Group 2

Alkali Earth Metals.

Alkali Earth Metals

Not as reactive as alkali metals, occur naturally only as compounds, have low density but greater density than alkali metals, and are silver in color. Examples include Beryllium, Magnesium, Calcium, Strontium, Barium, and Radium.

Groups 3-12

Transition Metals.

Transition Metals

Elements with higher density, greater strength, higher melting point, and are less reactive than alkali metals and alkaline earth metals.

Nonmetals

Elements with nonmetallic properties; good insulators (poor conductors).

Group 17

Halogens.

Halogens

Elements that react with metals to form salt.

Group 18

Noble Gases.

Noble Gases

Elements that react with other elements only under special conditions. Examples include Helium, Neon, Argon, Krypton, Xenon, and Radon.

Hydrogen

The most common element in the universe.

Metalloids

Elements that have physical and chemical properties of both metals and nonmetals. Examples include Boron, Silicon, Germanium, Arsenic, Antimony, Tellurium, Polonium, and Astatine.

Valence Electrons

Electrons on the outermost shell of an atom that create bonds with other atoms.

Groups (Periodic Table)

Tell how many valence electrons are in each element.

Periods (Periodic Table)

Tell how many electron shells each element has.

Reactivity of Halogens and Alkali Metals

Halogens (7 valence electrons) react aggressively with Alkali Metals (1 valence electron) because their combined 1+7 valence electrons create a stable octet (8).