Intro to the Periodic table and valence electrons

There are 3 main classes of elements: metals, nonmetals, metalloids. The Periodic Table

Outline the 3 groups on your Periodic Table: metals, nonmetals, metalloids. The Periodic Table

Metals, Nonmetals, & Metalloids Divide a piece of paper as shown Take notes on the following slides

metals nonmetals Located on left side of periodic table Located on right side of periodic table

metals nonmetals Solids at room temp. (except mercury) Most are gases (some brittle solids)

Metals nonmetals higher melting pointslower melting points

malleable (can be pounded & shaped) harder brittle (break easily) Softer than metals

Ductile (can be drawn into wire) Not ductile

metals nonmetals lustrous (shiny) metallic luster mostly silver or grayish white dull

Good conductors of heat and electricity Poor conductors (good insulators)

Metals nonmetals Tend to lose electrons form positive ions + Tend to gain electrons form negative ions -

Metals nonmetals Form ionic compounds with nonmetals Ionic bonds = transfer of electrons Form covalent compounds with other nonmetals Covalent bonds = sharing of electrons

Metalloids Have some properties of both metals & nonmetals Shiny, brittle solids Limited conductivity Located along stair step line in between metals & nonmetals Uses: semiconductors (Used in electronics), glass, alloys

Vertical columns Horizontal rows called groups or families. Elements in a group have similar chemical & physical properties. Numbered from 1-18 from left to right called periods. Elements within a period have properties that change progressively across the table. The Periodic Table

The group A elements are called the representative elements. 1A 8A 2A 2A 3A 4A 5A 6A 7A The Periodic Table

The group B elements are called the transition elements. The group B elements at the bottom are called the inner transition elements. Transition Inner Transition The Periodic Table

Group 1A Alkali metals 1 valence electron is lost easily, forms a cation (ions with a positive charge) with a 1+ charge. The group has similar physical properties Metallic appearance.

The Periodic Table Group 2A Alkaline earth metals 2 valence electrons that can be readily lost, forms a cation with a 2+ charge. The group has similar physical properties Metallic appearance.

The Periodic Table Group 7A Halogens (nonmetals) highly reactive with 7 valence electrons, forming an anion (a negatively charged ion) with a 1- charge

The Periodic Table Group 8A noble gases have a complete octet (8) of valence electrons they have little tendency to gain or lose electrons and are non-reactive.

The Periodic Table Group B transition metals in the middle of the Periodic Table Number of outer electrons varies, leading to a variety of charges for each element. they share many of their chemical and physical properties The Lanthanide series and the Actinide series, located at the bottom of the periodic table, are the inner transition metals (the rare earth metals).

Noble Gas Metalloids (on the stair-step line) Inner Transition Metals (f – block elements)

Label the following families on your Periodic Table The Periodic Table

The A group number = the number of valence electrons (except for He) 1A 2A3A4A5A6A7A 8A Valence electrons = the # of dots for Lewis Dot Diagrams Valence Electrons – outer electrons

The electron structure of an atom determines many of its chemical & physical properties. For the group A elements, the group number equals the number of valence electrons. (Except for Helium = 2) He Fill in the element symbols and valence electrons on the blank Periodic table Lewis Dot Diagrams

Using the Internet or a borrowed Chemistry class set of books research and create the assigned Periodic Families Poster Students will complete the worksheet summarizing the information found on each poster.

Complete the Stemscopes Periodic Table Activity

Make flash cards of the elements and polyatomic ions using either index cards, notebook paper or construction paper

Re-write the list by grouping all of the ones with similar charges together. Study with a partner for your quiz tomorrow. (You may use a Periodic table on the quiz)