Chemistry 11

“Wooot, yay, I love science”

“ Dmitri Ivanovich Mendeleev “

Certain characteristic properties of elements can be foretold from their atomic weights. – D.Mendeleev

The Periodic Table:Mendeleev - 1800’s

-63 elements known

-He recognized similarities in some of the elements

-Decided to group them according to mass and noticed a pattern in their bonding power or valence.

-When organized in this way the elements fell into columns which showed similar physical and chemical properties.

Your Turn To be a Scientist!!

• Your job is to arrange the fake elements you have been given according to the patterns you see and the trends you can create.

Modern Periodic Table

-When atomic numbers (number of protons in the nucleus) were discovered 50 years later the elements were arranged according to their atomic number.

-The periodic law states:

-other periods -calendars, music scales, periodicals.

Organization of the Periodic Table

Rows - called -elements in a period are not alike in properties.-1st element is an extremely active solid whereas

last element is a inactive gas ex. Columns - called

- elements in the same family have similar properties

ex. K, Na, Li are all soft, white, shiny metals.

Element key-

Metals - 88 elements to left of zigzag line are called metals.

Physical properties of metals:

• luster/shininess• good conductors of heat and electricity• • ductile-drawn into wires• malleable-hammered into thin sheets.

Chemical properties of metals:

• Tend to ex. rust/tarnish

Non-metals

- right of the zigzag line.

Physical properties:--

Chemical properties:-tend to

exception: Noble gases

Metalloids

- along both sides of the zigzag line are elements which have properties of both

ex. B, Si, Ge, As, Sb, Te, Po, At

Periodic Table

Chemical FamiliesMost Active MetalsAlkali Metals - elements in with one valence electron in their outermost energy level.- very reactive and readily bonded with other substances.

Ex.

Alkaline Earth Metals- elements in with two valence electrons in their outermost energy level. - still very reactive but not as reactive as Family 1 cause they have two electrons to get rid of.

Chemical Families

Transition Metals ( ) - have properties similar to one another and to other metals

-have one or two valence electrons in their outer shell.

-some have ability to an electron from their next to outermost energy level.

Chemical Families

From Metals to Non-Metals - five families to the right contain properties of metals as well as non-metals.

-named after the first element in the family.

Ex. c

Chemical Families

Halogens - have 7 valence electrons and are the most active of the non-metals.-react easily with alkali metals

Ex.

Noble Gases- , therefore normally unreactive.

Chemical Families

Rare-Earth Elements - two rows appearing at the bottom of the periodic table:

- lanthanoid series - soft malleable metals, high luster.

- actinoid series - radioactive, most made in lab.

Electron Configuration• The outer most electrons of an atom determines its

.

• These outer electrons are called .

• Elements in the same family/group have similar properties because they have similar valence electron configurations.

• Ex. Li=1s2 2s1Na=K=1s2s 2s2 2p6 3s2 3p6 4s1