So What is The Atom?

Mr. BarnerChemistry

Atoms in Space!

Three Major Particles

• J.J. Thompson Discovered Electron

• Used Cathode Ray Tube• Found in TV sets, computer monitors

• 1/2000 the mass of Hydrogen

• Negatively Charged – e-1

• First Sub-Atomic Particle• Each Element has a fixed number of

electrons

-1

Henry Mosely

• Positive Sub-Atomic Particles called Protons

• Every Atom of an Element has same Number of Protons

• Assigned Atomic Number

• Equal to # of Protons

• Identifies Element

•Modern Periodic Table

+1

James Chadwick

• Discovered a Neutral Particle - Neutron

• Was not affected by electric or magnetic forces.

• Atoms can have different amounts of Neutrons - Isotopes

Atom has Three Basic Particles

Atomic Number

Protons

+1 Charge

1 mass unit

Electrons

-1 Charge

1/2000 mass units

Mass Number =

Protons +Neutrons

Neutrons0 charge1 mass unit

Element Symbols as Models

1021Ne

ElementSymbol

Atomic Number10 Protons

10 Electrons

Mass Number10 Protons + 11 Neutrons

Three Isotopes of HydrogenSame Element – Different Mass

Isotopes of Carbon have the same number of protons but different numbers of

neutrons.

The Atomic Weight Reflects the Abundance and Mass of Each Isotope.

Atomic Number is the Number of Protons or Electrons

Mass Number Tells How Protons and Neutrons

H - 1

C - 12

U - 238

Parts of an Atom

Complete the TableIsotope Atomic

Number Mass

Number Protons Neutrons

8135Br

81 123

12 25 92 41 31 15

7835Br

IonsCations – have a shortage of electrons

+1 charge means one less e-+3 charge means 3 less e-

Anions – have an excess of electrons-1 charge means one extra e--2 charge means 2 extra electrons

The charge is shown in superscript

22512

MgCharge +2

10 Electrons

12 Protons

12 Protons + 13 Neutrons

Parts of an IonComplete the Table

Isotope Atomic Number

Mass Number

Protons Neutrons Electrons

3517Cl

1-

15 31 18

15 33 18 20 41 18 47 60 46

3116S

2-

CationsCations:

1. _______________ charged particles

2. _______________ of electrons = positive charge

3. _______________ are +1 and

_______________ are + 2;

Aluminum is +3, Zinc is +2, and Silver is +1

4. _______________ Numerals in ( ) are added to all other Cation names.

POSITIVELY

SHORTAGE

GROUP 1

GROUP 2

ROMAN

22512Mg

26630 Zn

Name Symbol Protons Electrons Neutrons Mass Number

Magnesium 12 10 13 25

19 18 39

Nickel (II) 29

13 10 27

ANIONS1. _________________ charged

particles2. _________________ of electrons =

negative charge3. _________________ is -1,

_________________ is -2, and _________________ is -3

4. _________________ goes at the end of Anion names

NEGATIVELY

EXCESS

GROUP 17

GROUP 16GROUP 15

-ide

1199F

23216S

Name Symbol Protons Electrons Neutrons Mass Number

Fluoride 9 10 10 19

17 18 36

Phosphide 16

6 10 7

Quantum Model of the Atom

Central NucleusExtremely small~all the massAll the positive chargeProtons & Neutrons

The Nucleus Would be like a Baseball in the Center of the Houston Astrodome.

MOST of the atom is EMPTY space Most of the MASS is in the NUCLEUS The motion of the ELECTRONS provide the SIZE and

HARDNESS of the atom.

First Property

All electrons SPINThey can spin clockwise

Called an up spin - ↑They can spin

counterclockwiseCalled a down spin - ↓

North

North

Clockwise SpinCounter-clockwise Spin

Electron Spin

Orbitals Electrons form a CLOUD They move RANDOMLY Cannot predict exact LOCATION and

EXACT MOTION The clouds has specific shapes – ORBITALS The ORBITAL cloud is made from ONE or

TWO electrons ORBITAL DIAGRAMS 2 Electron cloud ( ↑↓)

1 electron clouds (↑ ) OR ( ↓)

Orbitals can come in different shapes

“s” shape “Simple” shape Spherical Can hold up 2 electrons Lowest energy

The next shape – “p” Three similar orbitals Each orbital is along a 3-D axis Each orbital have up to 2 electrons Slightly higher energy than “s” orbital

2py

2pz

2px

The third shape – “d” 5 different orbital shapes 4 of the orbitals look like 4-leaf clovers 5th orbital looks like a fan blade with a

ring Each orbital can have up to 2 electrons Total of 10 electrons

“d” orbitals

z-axis

x-axis

y-axis

“d” orbitals

z-axis

x-axis

y-axis

z-axis

x-axis

y-axis

dz2

dxy

dxz

dyz

dx2 - y2

The forth shape – “f”• Very complex shapes

• There are 7 shapes that are called “f” orbitals

• They all have the same energy at the same size

• Each “f” orbital can have up to 2 electrons

• Total of 14 electrons

Seven “f” shapes

Seven “f” shapes

Seven “f” shapes

Seven “f” shapes

Seven “f” shapes

Seven “f” shapes

Seven “f” shapes

Putting Electrons in Orbitals

• Only at most two electrons in an orbital - ↑ and ↓• Orbitals of same shape are made

with one electron before pairing.( ) ( ) ( ) is OK

Three orbitals with electrons of same spin

() ( ) ( ) Must make third orbital before pairing

Orbitals together make aSublevel

• The “s” sublevel• Only one orbital –

spherical• Maximum of 2

electrons• The “p” sublevel• Made of the three

orbitals• Maximum of 6

electrons

More sublevels

• The “d” sublevel• Made of the five

“d” orbitals• Maximum of 10

electrons• Very high energy

as very restrictive

More Sublevels

• The “f” sublevel•Made of the seven “f” orbitals

•Maximum of 14 electrons

•Highest energy as MOST restrictive

Finally we make a complete ENERGY LEVEL

• Each level surrounds the nucleus• The levels are numbered

1, 2, 3, 4, 5 … n• The levels get larger so can

hold “n” sublevels

Energy Levels

• Level n = 1•Only 1 sublevel

•Titled 1s•1st Level, “s” sublevel

Energy Levels

• Level n = 2•Contains 2

sublevels• 2s = 2nd Level,

“s” orbital• 2p = 2nd Level,

“p” orbitals

Energy Levels

• Level n = 3

•Contains 3 sublevels• 3s = 3rd level, “s” orbital

• 3p = 3rd level, “p” orbitals

• 3d = 3rd level, “d” orbitals

Energy Levels

• Level n = 4

•Contains 4 sublevels• 4s = 4th level, “s” orbital

• 4p = 4th level, “p” orbitals • 4d = 4th level, “d” orbitals • 4f = 4th level, “f” orbitals

Levels, Sublevels & OrbitalsLevels Sublevels Orbitals Electrons

1st s only 1s2 2

2nd s & p 2s2 2p6 8

3rd s, p & d 3s2 3p6 3d10 18

4th s, p, d & f 4s2 4p6 4d10 4f1432

Complete the chart up to n = 7!

After f comes g, h, and i

Placing Electrons into the Atom

Tempe AZ Town Hall is Like an Atom Fill the Levels Top to Bottom

Filling an Orbital Diagram• ( ) represents an orbital, electron cloud

• ↑↓ represent the electron placed in an orbital

• Fill Orbitals from lowest energy to highest energy

• Orbitals of same energy are given one electron at a time BEFORE pairing

• Simple orbitals of larger clouds are less energy than complex orbitals

• 4s < 3d

• 6s < 4f

Electron Configuration

• Shows the levels and sublevels formed by the electrons - 1s 2s 2p• Considers that 4s < 3d and 5s < 4d• Use superscripts to show the number

of electrons in each sublevel• Total of superscripts is the Atomic

Number• 1s2 2s2 2p6 3s2 --> = 12, Mg

Diagonal Rule1s2

2s2

3s2

4s2

5s2

6s2

7s2

2p6

3p6

4p6

5p6

6p6

7p6

3d10

4d10

5d10

6d10

7d10

4f14

5f14

More Configurations

9F 1s2 2s2 2p5

11Na 1s2 2s2 2p6 3s1

14Si 1s2 2s2 2p6 3s2 3p2

18Ar 1s2 2s2 2p6 3s2 3p6

19K 1s2 2s2 2p6 3s2 3p6 4s1

22Ti 1s2 2s2 2p6 3s2 3p6 4s2 3d2

29Cu 1s2 2s2 2p6 3s2 3p6 4s2 3d9

33As 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p3

Terminar

All the Energy LevelsDiagonal Rule

1s2

2s2

3s2

4s2

5s2

6s2

7s2

2p6

3p6

4p6

5p6

6p6

7p6

3d10

4d10

5d10

6d10

7d10

4f14

5f14

6f14

7f14

LevelSublevel Maximum

Electrons

Filling LevelsDetermine how many levels

Equals the Period NumberDetermine how many electrons

in outer orbit1 or 2; 3-8 for Groups 13-18

Fill orbits from lowest upward to capacityCapacity = 2(n2)

Orbit Diagrams

OxygenNeonMagnesiumPhosphorousSiliconCalcium

IronZincChlorineAluminumBoronArgon

SublevelsDetailed analysis of the colors show subdivisionsThese sublevels tell us what region around the atom the electron is

usually located.Each level has a number of sublevels = # of level

“s” sublevel“Simple” shapeSphericalCan hold up 2

electrons3s2 is 3rd level,

“s” sublevel with 2 electrons

5s1 ?

2s2 ?

“s” shape for each Primary Level

n = 1 1s sublevel

n = 2 2s sublevel

n = 3 3s sublevel

“p” sublevelMade of three shapesEach shape is along a 3-D

x, y, or z axisCan have up to 6 total

electronsSlightly higher energy than

“s” sublevel3p4 means 3rd level, “p”

sublevel with 4 electrons

5p3 ?

3p2 ?

1p2 ?

Higher “p” sublevels

n = 1 has NO “p” sublevelsn = 2 2p

sublevel

n = 33p

sublevel

“d” sublevel Made of 5 shapes 4 of the shapes look like 4-leaf

clovers 5th shape looks like fan blade with a

ring Can have up to 10 electrons Because it is so complex it requires

more energy than next level with “s” sublevel3d > 4s, 5d > 6s

dz2

“d” shapes

z-axis

x-axis

y-axis

z-axis

x-axis

y-axis

z-axis

x-axis

y-axis

“f” sublevel Very complex shapes There are 7 shapes that make up “f”

sublevel “f” sublevel may have up to 14 electrons “f” sublevel requires more energy than

next higher “s” sublevel and second higher “p” sublevel4f > 6s & 5p5f > 7s & 6p

Orbitals Magnetic fields showed that sublevels were

made of individual clouds - orbitals Each Orbital has up to two electrons The orbital shows the orientation of the

cloud along or between the x,y,z axis Each orbital in a level has the same energy

“p” sublevel orbitals

px pz py

Levels, Sublevels & OrbitalsLevels Sublevels Orbitals Electrons

1st s only 1s2 2

2nd s & p 2s2 2p6 8

3rd s, p & d 3s2 3p6 3d10 18

4th s, p, d & f 4s2 4p6 4d10 4f1432

Complete the chart up to n = 7!

After f comes g, h, and i

LevelsElectron Levels

Clouds or ShellsIncreasing size and energyNumbered 1,2,3,4,5, ...Each Level holds 2(n2) electrons

Level 1 holds 2(12) = 2 e-Level 2 holds 2(22) = 8 e-Level 3 holds 2(32) = ___Level 5 holds _______ e-

Configurations and the Periodic Table

Li has 3 electrons1s2 2s1

Sodium has 11 electrons1s22s22p63s1

Potassium has 19 electrons1s22s22p63s23p63d1 BUTPotassium as 4 levels ending with 1 valance electron SO1s22s22p63s23p64s1

Arrange the levels by energy

4s is simpler and less energy than 3d so it comes first

After 3d then continue to 4p5s is less than 4d6s is less than 4f and 5d7s is less than 5f and 6d

Correct Order of Energy

Sublevels

Periodic Table w/ Sublevels

Configuration of Sulfur

1s2

2s2 2p6

3s2 3p4

Configuration for Iron1s2

2s2 2p6

3s2 3p6

4s2 3d6

Configuration for Gd

Use the Table to find the configuration of electrons

ClMgCuGeTeAu

1s22s23s23p5

1s22s22p63s2

1s22s23s24s23d9

1s22s23s24s23d104p2

1s22s23s24s23d104p65s24d105p4

1s22s23s24s23d104p65s24d105p6 6s2 4f14 5d9

Compounds

There is special stability if an atom has 8 valance electrons

Octet RuleMetals tend to lose electronsNonmetals tend to gain electrons

Atomic Size

In a group size increases as there are more levels

In a period size decreases as the greater positive nucleus draws in the valance electrons

Orbital = Electron cloud made by one or two electrons

Both electrons must have opposite spins!() is OK – opposite spins() is NOT OK – same spin