The Periodic Table I.History II.Arrangement of Elements III.Periodic Trends

Dimitrii Mendeleev ( Russian) (father of modern periodic table) Published system used today (1869) 2. Elements arranged by increasing mass 3. Left spaces for elements not yet discovered – predicted properties (scandium, gallium, germanium)

II. Arrangement of Elements A.Periodic Table - arrangement of elements in order of increasing atomic number so that elements with similar properties are in the same column PERIOD – horizontal row (7) FAMILY/GROUP vertical columns (1-18/1-8A) Periodicity - reoccurrence of similar properties of elements in groups

FAMILY / GROUP (1-18 / 1A – 8A) PERIOD (1-7)_

C. Special Groups on the Periodic Table ALKALIMETALSALKALIMETALS ALKALINEMETALSALKALINEMETALS TRANSITIONAL METALS NOBLEGASESNOBLEGASES HALOGENSHALOGENS BORONFAMBORONFAM CARBONFAMCARBONFAM NITROGENFAMNITROGENFAM OXYGENFAMOXYGENFAM

Reactivity A.Reactivity – measure of the tendency of an element to engage in chemical reactions by losing, gaining or sharing electrons 1. atoms of reactive elements are very likely to gain, lose or share electrons 2. atoms of reactive elements are likely to form chemical bonds with other elements

B. Reactivity and the Periodic Table 1. alkali metals (group 1) most reactive metals 2. alkaline earth metals (group 2) second most reactive group of metals 3. halogens (group 7A/17) most reactive nonmetals 4. noble gases (group 8/A18) least reactive Use the slides below to LIST a few properties each Family shares.

ALKALI METALS (Group 1A)

ALKALINE METALS (Group 2A)

TRANSITIONAL METALS (Groups 3-12)

BORON FAMILY (Group 3A)

CARBON FAMILY (Groups 4A)

NITROGEN FAMILY (Groups 5A)

OXYGEN FAMILY (Groups 6A)

HALOGENS (Group 7A/17)

NOBLE GASES (Group 8A/18)