Periodic Properties

SPS4a Determine the trends of the following: • Number of valence electrons • Types of ions formed by representative elements • Location of metals, nonmetals, and metalloids • Phases at room temperature Periodic Properties SPS4b Use the Periodic Table to predict the above properties for the representative elements.

Groups • The group number is the number assigned to a verticalcolumn on the periodic table. • Another name for group is a Family • There are 18 groups in the periodic table. • Groups 1, 2, 13 – 18 are representative

Periods • 1. The period number is the number assigned to a horizontalrow on the periodic table. • 2. The number of protons increase from left to right across a period. • 3. This number is the atomic number. • The period number indicates how many energy levels (rings) each atom has.

Hydrogen • Hydrogen belongs to a family of its own. • Hydrogen is a diatomic, reactive gas. • Hydrogen was involved in the explosion of the Hindenberg. • Hydrogen is promising as an alternative fuel source for automobiles http://www.youtube.com/watch?v=xiAT9xvTVKI&safety_mode=true&persist_safety_mode=1

METALS • shiny-luster • solids (except Hg) • malleable • ductile (stretch to wire) • conduct heat & electricity • most elements are metals

NONMETALS • solids, liquids & gases • luster-dull • brittle • poor conductors • upper-right hand corner (& H)

Metalliods • along stairstepline – between B & Al (Al is not a metalloid!) • classified as nonmetals but conduct heat and electricity under certain conditions • some metal & nonmetal properties

Alkali Metals Periodic Family Names Alkaline Earth Metals Nobl e gases Halogens (D- Block) <---Transition Metals-----------> (F—block) <-----------------Inner transition------------------>

Group 1 - Alkali Metals • soft, shiny • reacts violently with water • VERY reactive, one valence e- to lose; • cation

Alkali metals • http://www.youtube.com/watch?v=m55kgyApYrY&safety_mode=true&persist_safety_mode=1

Group 2 - Alkaline Earth Metals • 2 valence e-; cation • reactive

http://www.youtube.com/watch?v=m55kgyApYrY&safety_mode=true&persist_safety_mode=1http://www.youtube.com/watch?v=m55kgyApYrY&safety_mode=true&persist_safety_mode=1

Transition Metals • Elements in groups 3-12 • Less reactive harder metals • Includes metals used in jewelry and construction. • Metals used “as metal.”

Transition Metals • Groups 3-12 • Ions change – changes properties • NOT REPRESENTATIVE!

Halogens • Elements in group 17 • Very reactive, volatile, diatomic, nonmetals • Always found combined with other element in nature . • Used as disinfectants and to strengthen teeth.

Halogens • -Group 17 • -1 ions, highly reactive • 7 valence e-

Noble Gases • Elements in Group 18 • Noble gases are usually unreactive. • This is because they have fullvalence shells. • Elements with full valence shells do not easily gain or lose electrons.

Noble Gas Stability • Atoms want to gain stability, like the noble gases. • Atoms will try to gain or lose electrons to have a full valence shell.

Noble Gases • Group 18 • unreactive, 8 valence e- • exist as single atoms, inert

Phases of Elements • 1. Liquids: You must know: Hg and Br • 2. Gases: Don’t memorize, but you need to know their general location. Gases are towards the right side of the periodic table. • 3. Solids: All metals, except Hg - mercury

Vocabulary to know • Valence electron: electrons in the outermost energy level (ring) • Cation: (+) charged ion • Anion: (-) charged ion

Why ions form... • To get as close to an “octet” as possible

Octet Rule • Atoms tend to share, gain or lose electrons to have a set of eight (8) electrons in their outer shell.

http://www.archive.org/details/hindenberg_explodes • http://www.vidicom-tv.com/tohiburg.htm

Periodic Properties