Periodic Table Families Adapted from Liz LaRosa Some images are from www.chem4kids.com www.middleschoolscience.com 2008

Learning Scale – I can … 4 – Differentiate between the various groups on the periodic table. 3 - Describe the various groups on the periodic table. 2 - Use the periodic table to determine the number of protons, neutrons, or electrons. 1 - Identify patterns on the periodic table.

Development of the Periodic Table In 1869, Dmitri Mendeleev noticed that patterns appeared when he arranged the elements in order of increasing atomic mass. In 1913, Henry Moseley rearranged the periodic table according to atomic number.

Discussion Why do you think that scientists changed how the periodic table was set-up?

Organization of the Table Horizontal rows are called periods. Vertical columns are called groups. Atomic Mass= # of protons and neutrons Atomic Number = # of protons (or # of electrons)

Characteristics of Metals Luster (shiny) Ductility (ability to be pulled into thin wires) Malleability (ability to be hammered) Conductor Almost all are solid at room temperature

Characteristics of Nonmetals Many are gases at room temperature. Solids are brittle No luster (dull) Good insulators

Characteristics of Metalloids Properties of both metals and nonmetals Semiconductor – conducts electricity at high temperatures, but not at low temperatures.

Discussion Compare and contrast metals and nonmetals.

Families on the Periodic Table Elements on the periodic table can be grouped into families bases on their chemical properties. Each family has a specific name to differentiate it from the other families in the periodic table. Elements in each family react differently with other elements.

ALKALI METALS Group 1 Hydrogen is not a member Soft and silvery metals Very reactive, esp. with water Conduct electricity 1 Valence electron Image: http://www.learner.org/interactives/periodic/groups2.html

ALKALINE EARTH METALS Group 2 White and malleable Reactive, but less than Alkali metals Conduct electricity 2 Valence electrons

TRANSITION METALS Groups in the middle (3-12) Good conductors of heat and electricity.

BORON FAMILY Group 13 3 Valence electrons Most are metals

CARBON FAMILY Group 14 4 Valence electrons Contains metals, metalloids, and a non-metal

NITROGEN FAMILY Group 15 5 Valence Electrons Contains metals, metalloids, and non-metals

OXYGEN FAMILY Group 16 6 Valence electrons Contains metals, metalloids, and non-metals Reactive

Halogens Group 17 7 Valence electrons All are non-metals Very reactive -react with metals to form salt often bonds with Group 1

Noble Gases Group 18 Gases Non-metals 8 Valence electrons = Full (except He = 2) Not reactive with other elements

Rare Earth Metals Lanthanides & Actinides Some are Radioactive The rare earths are silver, silvery-white, or gray metals. Conduct electricity

Discussion What patterns can you identify on the periodic table? Provide evidence.

Learning Scale – I can … 4 – Differentiate between the various groups on the periodic table. 3 - Describe the various groups on the periodic table. 2 - Use the periodic table to determine the number of protons, neutrons, or electrons. 1 - Identify patterns on the periodic table.