Why is the periodic table shaped that way?

We already know that the atomic number = number of protons(+)

We already know that the atomic number = number of protons(+)

know this… the atomic number (number of protons (+)) is how we identify each element!

and we already learned how to find the number of neutrons (o) in the center of each atom. N (o) = ATOMIC MASS – ATOMIC NUMBER

and we already learned how to find the number of neutrons (o) in the center of each atom. N (o) = ATOMIC MASS – ATOMIC NUMBER N (o) = 7 – 3…4 neutrons in a lithium atom

Hand-out “first twenty elements/atoms go here”

The first twenty elements here….

…are represented HERE. H He Li Be B C N O F Ne Na Mg Al Si P S Cl Ar K Ca

Take a moment to list the abbreviations for the first twenty elements in the periodic table. N(o)= He Li Be B C N O F Ne Na Mg Al Si P S Cl Ar K Ca

Below each element abbreviation, write their number of protons (+) & number of neutrons(o) in each atom’s nucleus H P(+)= N(o)= He Li Be B C N O F Ne Na Mg Al Si P S Cl Ar K Ca

Why doesn’t Hydrogen have any neutrons like all other elements??

Why doesn’t Hydrogen have any neutrons like all other elements? It only has ONE proton(+) it doesn’t need neutrons (o) to stick protonS(+) together!

staple this sheet to your notes during class…

We have already learned quite a bit about this Periodic Table.

We have already learned quite a bit about this Periodic Table.

but emaleigh wants to know: why is the periodic table shaped this way?

It’s shaped this way partly because our wall isn’t wide enough!

These two bottom rows actually all fit into the last two rows of group 3!

These two bottom rows actually all fit into the last two rows of group 3!

So really, the Periodic Table should look like this:

But regardless of wall space, WHY IS IT with 18 COLUMNS & 7 ROWS?

Haven’t we forgotten something? We’ve covered protons (+) and neutrons (o). Haven’t we forgotten something?

what can the periodic table tell us about those tiny, orbiting electrons(-)???

But they still can pack a punch. Electrons(-) jump between atoms easily, because they orbit on the outside of each atom. But they still can pack a punch.

But electrons (-) do not just randomly orbit around protons (+) and Neutrons (o). Noooooo.

just like our planets orbit the sun,

just like our planets orbit the sun,

just like our planets orbit the sun, tiny electrons(-) orbit around the atomic nucleus in distinct orbits.

LET’S LOOK AT THE FIRST TWENTY ELEMENTS AGAIN… hand-out 2nd sheet…

Let’s look at the first twenty elements again, but with all their electron (-) orbits.

What do you notice about electron (-) orbits? P(+)= N(o)= He Li Be B C N O F Ne Na Mg Al Si P S Cl Ar K Ca Number of ___________ (+) = ATOMIC __________ (top #) Number of protons (+) & neutrons (o) = ATOMIC ______ (bottom #) ATOMIC MASS – ATOMIC NUMBER = Number of ___________ (o) Protons (+) = electrons (-)…2 fit in 1st orbit, 8 in 2nd orbit, 8 in 3rd orbit

Go to the “How does the Periodic Table work part 4”

Grab an atom kit and get into your groups of 4

Let’s see each group make a model of the first 20 elements!

HYDROGEN…

HYDROGEN…

HELIUM…

HELIUM…

LITHIUM…

BERYLLIUM…

BORON…

CARBON…

NITROGEN…

OXYGEN…

FLUORINE…

NEON…

SODIUM…

MAGNESIUM…

ALUMINUM…

SILICON…

PHOSPHORUS…

SULFUR…

CHLORINE…

ARGON…

POTASSIUM…

CALCIUM…

GREAT! Now staple this sheet in your notes & don’t lose it!!!!