Periodic Table

8.5C interpret the arrangement of the periodic table, including groups and periods, to explain how properties are used to classify elements https://www.youtube.com/watch?v=v1TfPDlA1xE

A Little Periodic Table History…

History of the Periodic Table

• Dmitri Mendeleev, a Russian scientist born in Siberia in 1834, is known as the father of the periodic table of the elements

• The periodic table is designed to help you predict chemical and physical properties of elements

Key points are underlined, you might want to write them down!

Elements are arranged in order of increasing atomic number on the periodic table

Big Science Idea

Element Location• Elements are located in three main categories on the periodic table

based on their physical properties

• Metals

• Nonmetals

• Metalloids

Physical Properties

• Physical properties can be observed or measured without changing the composition of matter.

• Physical properties are used to observe and describe matter.

Examples of Physical Properties

Color/Texture

Malleable – Can be pounded/rolled into a shape

Mass – How much matter is in an object

Ductile – Can be stretched into a long wire

Density – How tightly mass is packed into an object

Metals, Nonmetals, & Metalloids

MetalsMost elements are metals. The 88 elements to the left of the

stairstep (or zig-zag) line are metals or metal-like elements.

Physical Properties of Metals:

– Luster (shininess)

– Good conductors of heat and electricity

– High density (heavy for their size)

– High melting point

– Ductile

– Malleable

Metals

Properties of Metals Demo

•Watch this!

Metals can be hit, bent or stretched because they are malleable and ductile.

Video on PT and Metals

• https://www.youtube.com/watch?v=0pdRxrmgRoQ

Check Point Question!

When you crush a steel can for recycling for stomping on it, it collapses down but does not fall apart or shatter. What is the best explanation for this?

• When force is applied the metal undergoes its brittle property

• When force is applied the metal is malleable and can be re-shaped

• When force is applied the metal undergoes its ductile property

• When force is applied the new shape makes it easier to recycle

Nonmetals

Nonmetals are found to the right of the stair-step line. Their characteristics are opposite those of metals.

• Physical Properties of Nonmetals:

• No luster (dull appearance)

• Poor conductor of heat and electricity

• Brittle (breaks easily)

• Not ductile

• Not malleable

• Low density

• Low melting point

Nonmetals

Metalloids

Elements on both sides of the zigzag line have properties of both metals and nonmetals. These elements are called metalloids.

Physical Properties of Metalloids:

• Solids

• Can be shiny or dull

• Ductile

• Malleable

• Conduct heat and electricity better than nonmetals but not as well as metals

Metalloids

Scientists organize elements according to their physical and chemical properties

Big Science

Idea

How to Read the Periodic Table

• The Periodic table is designed to help you predict what an element's physical and chemical properties are

• You can also predict what elements will bond with each other

Elements are arranged:Vertically into Groups (also called Families)

Horizontally Into Periods

If you looked at one atom of every element in a group you would see…

Why?

Each atom has the same number of electrons in it’s outermost shell.

Think back to the Bohr Model…

For example: The group 2 atoms all have 2 electrons in their outer shells

Be (Beryllium)

Atom

Mg (Magnesium) Atom

Valence Electrons

• Effect the way an atom bonds, which determines many of the chemical properties of the element, including reactivity• Atoms can have anywhere between 1 and 8 valence electrons

• This is why elements within a group usually have similar chemical properties

Check point!Potassium has properties most similar to which of these elements?

• Lithium (Li)

• Beryllium (Be)

• Calcium (Ca)

Chemical Properties

• A chemical property is a characteristic that is observed when a substance changes into a different substance.

Examples of Chemical Properties

Reactivity – undergoes a chemical reaction

Corrosion –destruction of metals

Oxidation – rusting or tarnishingFlammable – capable of

igniting

Combustible – capable of igniting at higher temps

Each group has distinct properties

• The periodic Table is divided into several groups based on the properties of different atoms

For example…

Alkali Metals

Soft, silvery colored

metals

Very reactive!!!

• https://www.youtube.com/watch?v=uixxJtJPVXk

Reactions with water!

Another checkpoint!