Introduction to the Periodic Table

Chapter 15-1

Today’s Periodic Table

Elements organized by increasing atomic number

Rows (periods) labeled 1-7Period—row of elements whose properties

change gradually and predictably18 columns (group or family)

Group—elements that have similar physical or chemical properties

Periodic Table

Divided into two sections1st Section: Groups 1-2 and Groups 13-

18Representative elements Include metals, nonmetals, metalloids

2nd Section: Groups 3-12Transition elementsAll metals

Metals

All metals are solid, with the exception of mercury

Most have high melting pointsHave luster (reflect light)Good conductor of heat and electricityMalleable (can be pressed or pounded

into thin sheets or shaped into objects)Ductile (can be drawn out into wires)

Nonmetals & Metalloids

Nonmetals Gases or brittle

solids Poor conductors of

heat and electricity 17 nonmetals Many essential for

life C, S, N, O, I

Metalloids Shares some

properties with metals and some with nonmetals

Also called semimetals

Element Keys

Box on periodic table to represent element

Symbols for Elements

One or two letter abbreviationsOften based on element nameSymbol might also come from Greek or

Latin names (Iron=Fe, latin for iron is ferrous)

Some elements named for scientistsOthers named for geographic locations

Symbols for Elements

New elements are given a temporary name and 3 letter symbol

Once discovery is verified, discoverers can choose permanent name