The Periodic tableThe Periodic table

The periodic table is a way of The periodic table is a way of keeping track of all of the elements. keeping track of all of the elements. Each element has a symbol. Some Each element has a symbol. Some symbols are only one capital letter symbols are only one capital letter (Example hydrogen – H), but some (Example hydrogen – H), but some sumbols are two letters. A two letter sumbols are two letters. A two letter element symbol is always a capital element symbol is always a capital letter followed by a small letter letter followed by a small letter (Example Calcium- Ca)(Example Calcium- Ca)

The Periodic TableThe Periodic Table

The periodic table is arranged in The periodic table is arranged in the way it is for a reason!the way it is for a reason!

Look at the imaginary periodic Look at the imaginary periodic table you drew Bohr diagrams on.table you drew Bohr diagrams on.

What do you notice about all the What do you notice about all the elements in the same column?elements in the same column?

The columns on The columns on the periodic table the periodic table are called are called groupsgroups or or familiesfamilies. .

Each family has the Each family has the same number of same number of electrons in their electrons in their outer shellouter shell. .

Each family also has a number (at Each family also has a number (at the top of the column). the top of the column).

This number is the same as This number is the same as # of # of outer shell electronsouter shell electrons. .

This is an easy way to double check This is an easy way to double check your work when drawing Bohr your work when drawing Bohr models.models.

Some of the important families have Some of the important families have names:names:

Alkali metals - Alkali metals - Group Group 11 Alkaline Earth Metals -Alkaline Earth Metals - Group Group 22 Chalcogens - Chalcogens - Group Group 6A6A (16)(16) Halogens - Halogens - Group Group 7A7A (17) (17) Noble Gases - Noble Gases - Group Group 8A8A (18) (18)

The families react the same way, The families react the same way, chemically, in most situations.chemically, in most situations.

The only difference is, as you go The only difference is, as you go further down the periodic table, they further down the periodic table, they get more reactive.get more reactive.

How quickly and strongly something How quickly and strongly something reacts with something else is called reacts with something else is called reactivityreactivity..

The rows The rows acrossacross the periodic table the periodic table are also numbered.are also numbered.

There are called rows or There are called rows or periodsperiods (hence the name).(hence the name).

Look at your Bohr models again. Look at your Bohr models again. What do you notice about the What do you notice about the numbers of rows?numbers of rows?

That’s right!! The number of the rows That’s right!! The number of the rows is equal to the is equal to the # of shells# of shells we need we need to put electrons in.to put electrons in.

Another easy way to check your Another easy way to check your work! work!

Now look at the periodic Now look at the periodic table in the back of your table in the back of your text.text.

Green symbols represent Green symbols represent metalsmetals..

Think about metals you Think about metals you have seen. List some have seen. List some properties of metals.properties of metals.

ShinyShiny DuctileDuctile MalleableMalleable

Conduct heat & Conduct heat & electricityelectricity

The orange The orange elements are called elements are called non-metalsnon-metals..

List some properties List some properties of non metals.of non metals.

DullDull BrittleBrittle Poor conductors Poor conductors

(insulators)(insulators)

The purple The purple elements are called elements are called metalloidsmetalloids..

This means that This means that they sometimes they sometimes act like metals, and act like metals, and sometimes act like sometimes act like non-metals. They non-metals. They can’t make up their can’t make up their minds!minds!

Right through the metalloids runs Right through the metalloids runs something called the something called the staircasestaircase. .

This separates metals (on the left This separates metals (on the left side) from the non-metals (on the side) from the non-metals (on the right side).right side).