The Periodic TableJ. McLeod

H. Chemistry

Essential Question

How is the periodic table arranged?

A little history…

Dmitri Mendeleev: 1st Periodic Table organized the periodic table by increasing atomic massLeft empty spaces Predicted properties of unknown elements

Mendeleev’s Table

A little more history...

Henry Moseley: Modern Periodic Table (1887-1915) There were small problems with Mendeleev’s table. Used information he found about isotopes to modify Mendeleev’s table Determined that elements are put in order by their atomic number

Elements are arranged:

Vertically into Groups/Families

Horizontally Into Periods

Why?

If you looked at one atom of every element in a

group you would see…

Each atom has the same number of valence electrons Electrons in the outermost energy level (shell)

The group 2 atoms all have 2 electrons in their outer shells

Be (Beryllium)

Atom

Mg (Magnesium) Atom

The number of outer or valence electrons in an atom effects the way an atom bonds.

The way an atom bonds determines many properties of the element.

This is why elements within a group usually have similar properties.

If you looked at an atom from each element in a period you would see…

Each atom has the same number of energy levels.

The period 4 atoms each have 4 energy levels

K (Potassium) Atom

Fe (Iron) AtomKr (Krypton)

Atom

4th Shell

Divisions of the Table

The Periodic Table is divided into regions based on general propertiesInclude:

Metals Non-metals Metalloids

Left side of the stairs Forms cations by losing electrons High Melting Points Solids at room temperature (except Hg) Metallic luster Malleable and ductile Good conductors of heat and electricity

Metals

Non-metals

Right side of the stairs Forms anions by gaining electrons Low Melting Points Gases or solids at room temperature

(except Br2) Brittle solids (Which means what?) Insulators (poor conductors or heat &

electricity)

Metalloids Have properties of both metals and non-metals Semi-conductors Solids

Ticket Out The Door:

State whether the following are metals, nonmetals, or metalloids and then predict a property that they may have: Potassium Iodine Antimony

Bellwork

What are the vertical columns of the PT called? What do they have in common?

What are the horizontal rows called? What do they have in common?

Groups

Hydrogen

Belongs to a family of its own.

Is a diatomic, reactive gas.

Was involved in the explosion of the Hindenberg.

Is promising as an alternative fuel source for automobiles

Group 1Soft, silvery colored metals1 valence e-Very reactive!!!

Alkali Metals

Alkali Metal Video

What trend in reactivity is seen amongst the alkali metals?

What would you expect from Francium?!?!

Alkaline Earth Metals Group 2 Silvery-white metals 2 valence e-

Fairly reactive Many are found in rocks in the earth’s

crust

Transition Metals

• Most are good conductors heat & electricity

• Malleable (easily bent or hammered into wires or sheets)

How many things can you think of that have Transition Metals in them?

Write as many down as you can in 1 minute.

Halogens

Group 17 Have 7 Valence electrons Most are poisonous Cl2 was used as a chemical weapon

during WWI and WWII

Halogens

What trend in reactivity is seen amongst the Halogens?

Noble Gases

Group 18 8 Valence Electrons Very unreactive Gases at room temperature

Jellyfish lamps made with noble gases artist- Eric Ehlenberger

Lanthanide Series

Actinide Series

Lanthanides & ActinidesLocated at the bottom of the Periodic TableRare Earth Metals

Summing it up: Ticket out the Door

State which group each of the following elements belongs to and give a property of the element.

Lithium Chlorine Uranium Krypton Strontium Chromium

Bellwork

1. What is the most reactive metal?2. What is the most reactive nonmetal?3. How many energy levels does

Strontium have?4. How many valence electrons does

Aluminum have?

Blank Periodic Table

Write the names of the families in their respective columns Alkali Metals, Alkaline Earth Metals, Halogens, & Noble

Gases Label the two rows with their respective names

Lanthanides & Actinides Outline the metals in RED Outline the metalloids in GREEN Outline the non-metals in BLUE Draw an arrow showing reactivity of METALS Draw an arrow showing reactivity of NONMETALS

The properties of the elements on the periodic table create trends as you move around.

Trends move left-right & up-down

Periodicity

Reactivity of Metals

Towards Francium

Fr

Reactivity of Nonmetals

Towards Fluorine

F

- ½ the distance between two adjacent nuclei

…increases as we go down a column

WHY? add a new energy level each time

…increases as we go right to leftacross a period

WHY? Decrease in nuclear charge

Atomic Radius

Atomic RadiiLi

Na

K

Rb

Cs

ClSPSiAl

BrSeAsGeGa

ITeSbSnIn

Tl Pb Bi

Mg

Ca

Sr

Ba

Be FONCB

1.52 1.11

1.86 1.60

2.31 1.97

2.44 2.15

2.62 2.17

0.88 0.77 0.70 0.66 0.64

1.43 1.17 1.10 1.04 0.99

1.22 1.22 1.21 1.17 1.14

1.62 1.40 1.41 1.37 1.33

1.71 1.75 1.46

IA IIA IIIA IVA VA VIA VIIA

= 1 Angstrom

cations anions Ca atom Ca+2 ion Cl atom Cl-1 ion

the size of an ion

20 p+

20 e–

20 p+

18 e–

17 p+

17 e–

17 p+

18 e–

Ca Ca2+ Cl Cl1–

cations lose electrons-smaller

Anions gain electronslarger

Ionic Radius

IA IIA IIIA IVA VA VIA VIIA

0.60 0.31

0.95 0.65

1.33 0.99

1.48 1.13

1.69 1.35

1.71 1.40 1.36

0.50 1.84 1.81

0.62 1.98 1.85

0.81 2.21 2.16

0.95

Li1+ Be2+

Na1+ Mg2+

Cl1-

N3- O2- F1-

S2-

Se2- Br1-

Te2- I1-

Al3+

Ga3+

In3+

Tl3+

Ca2+K1+

Sr2+Rb1+

Cs1+ Ba2+

Li

Na

K

Rb

Cs

ClSPSiAl

BrSeAsGeGa

ITeSbSnIn

Tl Pb Bi

Mg

Ca

Sr

Ba

1.52 1.11

1.86 1.60

2.31 1.97

2.44 2.15

2.62 2.17

0.88 0.77 0.70 0.66 0.64

1.43 1.17 1.10 1.04 0.99

1.22 1.22 1.21 1.17 1.14

1.62 1.40 1.41 1.37 1.33

1.71 1.75 1.46

Be B C N O F

= 1 Angstrom

AtomicRadii

IonicRadii

Cations: smaller than parent atoms

Anions: LARGERthan parent atoms

– the energy required to remove an e– from an atom …increases as we go up a column

WHY? shielding effect - increase in the number of energy levels

…increases as we go from left to right across a periodWHY?

Nonmetals tend to gain electrons… high 1st ionization energy. Metals tend to lose electrons… low first ionization energy

Ionization Energy

Ionization Energy increases He

– the tendency for a bonded atom to attract electrons to itself

…increases as we go up a column

…increases as we go left to right across a periodWHY?

Nonmetals tend to gain electrons… high electronegativity

Metals tend to lose electrons… low electronegativity

Electronegativity

electronegativity increases F

On the periodic table on the next page of your notes… draw out all of the trends if you have not done so already.

Periodic Table