Made the FIRST periodic table - Ms. Thompson's...

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Made the FIRST periodic table

1869 Mendeleev organized

the periodic table based on

the similar properties and

relativities of certain

elements

Later, Henri Moseley

organized the elements by

increasing atomic number

Periodic Table

CaK Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr

Periods: the rows in the

periodic table

Groups: the

columns in the

periodic table

Elements in the

same group have

similar chemical

properties

Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr

XeITeSbSnInCdAgPdRhRuTcMoNbZrY

Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn

Db Sg Bh Hs Mt

LuYbTmErHoDyTbGdEuSmPmNdPrCe

Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr

ClSPSiAl

B C N O

Main Group or

Representative

Elements

Db Sg Bh Hs Mt

ClSPSiAl

B C N O

Transition

Metals

Db Sg Bh Hs Mt

ClSPSiAl

B C N O

Lanthanide Series

Db Sg Bh Hs Mt

ClSPSiAl

B C N O

Actinide Series

ALKALI METALS

ALKALINE EARTH METALS

CHALCOGENS

HALOGENS

NOBLE GASES

Db Sg Bh Hs Mt

ClSPSiAl

B C N O

Alkali Metals

Db Sg Bh Hs Mt

ClSPSiAl

B C N O

Alkaline Earth

Metals

Db Sg Bh Hs Mt

ClSPSiAl

B C N O

Halogens

Db Sg Bh Hs Mt

ClSPSiAl

B C N O

Noble Gases

METALS

METALLOIDS

NONMETALS

Metals

Left side of the periodic table

except H

Properties:

lustrous (shiny)

good thermal and electrical conductors

malleable

solids at RT

except Hg = liquid

Non-Metals

Right side of table

plus H

Properties:

Dull appearance

Brittle when solid

Do not conduct heat or electricity well

Primarily solids or gases at RT

Bromine = liquid

Metalloids

Stair step between metals and non-metals

Properties in between metals and non-metals

Si: brittle but semi-conductor

1. Aufbau Principle - an electron occupies the lowest-energy orbital that can receive it

2. Pauli Exclusion Principle - no two

electrons in the same atom can have the

same set of four quantum numbers

**Opposite spin states!!**

3. Hund’s Rule – orbitals of equal energy are each occupied by one electron before any orbital is occupied by a second electron, and all electrons in singly occupied orbitals must have the same spin state

Each electron has its own orbital

All are in the same spin state

Shortcut (shortened) Notation:

Use closest Noble Gas before the element

For bromine:

Closest Noble Gas before the element:

Argon:

Shortcut Notation:

1s22s22p63s23p6

[Ar] 4s23d104p5

4s23d104p5

• For sodium:

• For potassium:

[Ne]3s1

[Ar]4s1

1 valence electron!

For aluminum:

For gallium:

[Ne]3s23p1

[Ar]4s23d104p1

3 valence electrons!

For chlorine:

For bromine:

1s22s22p63s23p64s23d104p5

1s22s22p63s23p5

7 valence electrons!

A way to represent the number of valence

electrons an atom contains

Number of Electrons in the

Ending Configuration

Lewis Dot Diagram

Number of Electrons in the

Ending Configuration

Lewis Dot Diagram

A few exceptions:Chromium

Would expect: 1s22s22p63s23p64s23d4

Actually: 1s22s22p63s23p64s13d5

1s 2s 2p 3s 3p

Periodicity – We can tell a lot about

particular properties of elements

simply based upon where they are on

the periodic chart.

There are five general trends that

can be predicted: atomic size,

ionization energy, electronegativity,

electron affinity, and reactivity.

It all relates to something called effective nuclear charge Zeff.

Think of the effective nuclear charge as the pull that the outer electrons feel from the nucleus.

Nuclear pull: The pull/attraction between the + protons and the – electrons.

Atomic Radius

Measures the size of an atom

Measured from one nucleus to the next

K has 19 +

charges

Br has 35 +

charges

As you go from left to right, the pull on the

outer electrons (from the nucleus) is greater. It

requires more energy to hold onto those

electrons, which causes the atomic size to be

smaller.

ATOMIC SIZE DECREASES

As you move

down the chart,

the number of

energy levels

increases.

Therefore, as you move down the chart the atomic size

increases.

http://encarta.msn.co

Ignore noble gases when going left to

right.

Memorize fluorine as the smallest

element on the chart.

Memorize francium as the largest

element on the chart.

Ionic Radius

The size of ions (charged atoms resulting from a change

in electrons)

+: Cation: lost electron(s)

-: Anion: gain electron(s)

+2 < +1 < 0 < -1 < -2

•The amount of energy required to remove

valance electrons.

•The amount of energy required to create an

•The greater the effective nuclear charge (Zeff),

the tighter the valance electrons are being held.

•The tighter the electrons are being held, more

energy is required to remove them.

The amount of energy required to remove the

outermost electron from an atom

http://nanotech.sc.mahidol.ac.th/genchem/bonding1/ie.jpghttp://www.physchem.co.za/Atomic/Periodicity.htm

Zeff increases

Ionization Energy increases

Effective nuclear

charge decreases

(Zeff).

Ionization energy

decreases.

As the valance electrons get farther away, the force of attraction (Zeff)

between the nucleus and the electrons gets weaker. Thus, less energy is

required to remove the electrons. F will have the highest IE and Fr will

have the lowest.

• Affinity tends to increase across a period

• Affinity tends to decrease as you go down

a group

•Electrons farther from the nucleus

experience less nuclear attraction

•Some irregularities due to repulsive

forces in the relatively small p orbitals

Zeff increases

Electron Affinity increases

Effective nuclear

charge decreases

(Zeff).

Electron Affinity

decreases.

The attraction an atom has for an electron in a

Increases with an increased effective nuclear

charge.

Decreases

with a

decreased

effective

nuclear

charge.

Defined as how easily an atom can lose or gain

electrons in order to complete the octet.

Metals will lose electrons until they’re left with

8 valance.

Nonmetals will gain electrons until they’re left

with 8 valance.

Metalloids can do both.

Since metals lose electrons, reactive metals are those

metals that can easily lose their electrons.

Reactivity decreases with increased

Reactivity

increases

decreased

Nonmetals gain electrons to complete the

octet.

Smaller nonmetals can gain electrons easier

than larger nonmetals due to an increased

effective nuclear charge (Zeff).

Summation of Periodic TrendsZeff, IE, and EN follow the same trends. Atomic Radius is opposite.

Electronegativity

Made the FIRST periodic table - Ms. Thompson's...

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