The Periodic Table

Father of the Periodic Table

In the early 1800s several scientists tried to organize the elements

In 1869 Dmitri Mendeleev was able to arrange elements by their chemical properties, using rows and columns

We call this table periodic because it shows a periodic, repeating pattern of properties of the elements.

Reading the Periodic Table

Atomic number

Atomic mass

Element nameChemical symbol1313AlAl

26.98126.981AluminumAluminum

Pop Quiz Question #1

Who is Dmitri Mendeleev?

A. He discovered the most elements.

B. He created the periodic table

C. He named the periodic table

D. He discovered Mendelevium (atomic number 101)

Groups and Periods

Elements in a vertical column have similar physical and chemical properties

Vertical columns are called groups or families

The chemical properties of elements in horizontal rows show a progression

Horizontal rows are called periods

Pop Quiz Question #2

Which way is a group organized?

A. A group is a row.

B. A group is a column.

Trends on the Periodic Table

Sizes of the atoms decrease as we move from left to right across a period

This is due to the increasing number of protons in the nucleus, so the electrical attraction between the nucleus and the orbiting electrons gets stronger and pulls the electrons closer to the nucleus

Atom size decreasesAtom

size increases

Pop Quiz Question #5

How does the size of atoms change as you go from left to right across the periodic table?

A. Atoms get larger moving left to right

B. Atoms get larger moving right to left

C. Atoms get larger moving down a group

D. Atoms get larger moving up a group

Three Main Regions

Metals –on the left

Metalloids –stair steps

Nonmetals – on the right

Characteristics of Most Metals

ShinyMalleable and ductile (can be shaped

into sheets and wires)Good conductors of heat and electricitySolid at room temperature (except

Mercury)

Alkali Metals

Soft, silvery colored metals

Very reactive!!!

Alkali Metals reacting with water:

Li (Lithium) Na (Sodium) K (Potassium) Rb (Rubidium) Cs (Cesium)

What would you expect from Francium?!?!

Alkaline Earth Metals

Silvery-White Metals (shiny)

Fairly reactive

Many are found in rocks in the earth’s crust

Transition Metals

Malleable Conductors of heat/ electricity

&

Pop Quiz Question #6

What are the three main parts to the periodic table?

A. Solids, liquids, gases

B. Protons, neutrons, electrons

C. Metals, nonmetals, metalloids

How many things can you think of that have

Transition Metals in them?

Metalloids lie on either side of these “stair steps”

They share properties with both metals and non-metals

Si (Silicon) and Ge (Germanium) are very important “semi-conductors”

What are semiconductors used in?

Nonmetals

Brittle

Do not conduct electricity

Most are Poisonous

Fairly reactive

Halogens

Chlorine Gas was used as a chemical weapon during World War I.

It was used by the Nazis in World War II.

Halogen Uses

Unreactive

Gases at room temperature

Noble Gases

Neon Signs with Noble Gases

Neon Argon Helium

Krypton Xenon

Actinide SeriesRare Earth metalsLanthanide Series

Radioactive metals

The Elements Song

Sung by Tom Lehrer, from the 1959 periodic table