Comparing Atoms

REVIEW

2 or more types of matter

1 type of matter

OUR FOCUS in CH 4-7

2 or more types of matter

1 type of matter

Steps 1 - 8

• Started out DEEP MAROON / RED• Mass crucible 25.078 g• Mass of crucible & Cu 26.558 g• Heat Copper (2 min) re-mass ????

What happened to the mass????

Copper Lab

Steps 1 - 8• Started out DEEP MAROON / RED• Mass crucible 25.078 g• Mass of crucible & Cu 26.558 g• Heat Copper (2 min) re-mass 26.572 g

+ + + +

Ended solid BLACK

A major change!

Copper Lab

The red substance “rainbowed”, changed to black and gained mass. These three indicate the substance

underwent a

Chem

ical

chan

ge

Phys

ical

cha

nge

Nei

ther

0% 0%0%

1. Chemical change

2. Physical change

3. Neither

Steps 9-12

• Heat 15 min. longer• Hard solid formed–

hard to remove from the bottom of the crucible

• Some red still visible on the bottom side – mostly black though

• Observations:• Some still black and some

still red–Red is the original

copper that has not reacted.

–Black – is copper that reacted with ????

DAY 2 – Part A

Oxygen in the air

The black and red substance you broke up in the bottom of the crucible and transferred to an

empty test tube was

A p

ure s

ubstan

...

A m

ixtu

re o

f s...

0%0%

1. A pure substance

2. A mixture of substances

The red substance by itself was

A p

ure s

ubstan

ce

A m

ixtu

re

0%0%

1. A pure substance

2. A mixture

The red pure substance is a(n)

Element

Compound

0%0%

1. Element

2. Compound

Copper

An element

The black substance by itself was

A p

ure s

ubstan

ce

A m

ixtu

re

0%0%

1. A pure substance

2. A mixture

The black substance by itself is a(n)

Element

compound

0%0%

1. Element

2. compound

Copper II Oxide

A compound

2 Cu + O2 2 CuO

Which is/(are) elements?

Cu a

nd CuO

O a

nd CuO

Cu o

nly

O o

nly

CuO o

nly

Cu a

nd O

0% 0% 0%0%0%0%

1. Cu and CuO

2. O and CuO

3. Cu only

4. O only

5. CuO only

6. Cu and O

2 Cu + O2 2 CuO

Which is/(are) compounds?

Cu a

nd CuO

O a

nd CuO

Cu o

nly

O o

nly

CuO o

nly

Cu a

nd O

0% 0% 0%0%0%0%

1. Cu and CuO

2. O and CuO

3. Cu only

4. O only

5. CuO only

6. Cu and O

DAY 2 – Part A• Solution saved for

part B

• Mass the solid particles remaining from the HCl solution.

• Mass – the copper quantity has decreased. – Where is the copper?

GREEN

Copper now in the SolutionNOTE: a completely different phase of matter.

Which substance was soluble in HCl?

Cu –

red

subst

...

CuO –

bla

ck s

u...

Nei

ther

was

Both

wer

e

0% 0%0%0%

1. Cu – red substance

2. CuO – black substance

3. Neither was

4. Both were

CuO + HCl CuCl2 + H2O + Cu unreactedsolution

Which is/(are) elements?...compounds?

Elements – Cu

Compounds - CuO HCl CuCl2 H2O

• Zinc added to “saved solution”

• Bubbles • Bubbles• Bubbles• Color change• Red stuff precipitates

– Physical or Chemical Change?

DAY 2 – Part B

Chemical

• Reaction completed• Observe what is left

• Identify - COPPER

• Color - REDDISH• Squishy - YES

DAY 2 – Part B

CuCl2 + Zn ZnCl2 + Cu (Solution)

What Happened?

Zinc replaces copper in the solution and

copper precipitated

out

CuCl2 + Zn ZnCl2 + Cu

Which is/(are) elements?

CuCl2

and

Cu

CuCl2

and

ZnCl2

Zn a

nd ZnCl2

Zn a

nd Cu

0% 0%0%0%

1. CuCl2 and Cu

2. CuCl2 and ZnCl2

3. Zn and ZnCl2

4. Zn and Cu

CuCl2 + Zn ZnCl2 + Cu

Which is/(are) compounds?

CuCl2

and

Cu

CuCl2

and

ZnCl2

Zn a

nd ZnCl2

Zn a

nd Cu

0% 0%0%0%

1. CuCl2 and Cu

2. CuCl2 and ZnCl2

3. Zn and ZnCl2

4. Zn and Cu

CuCl2 + Zn ZnCl2 + Cu (Solution)

Zinc replaced copper in the

solution

Neither Heating nor other means breaks down copper

• ELEMENT• True of all elements!

Pure substance with one type of atom.

• LIME=?? • 1800 Battery• 1807=H.Davy used

battery to decompose (electrolyze) metal oxides (= Ca)

• Later Muriatic Acid broken down to find Cl

Today’s Element List

• 50 commonly used • 10 = 99% of the mass

of the Earth (5=92%)

(O,Si,H, Al, Fe, Ca,Na,Mg, Cl,K)

Scientists to Know …

DALTON

BOHR

CHADWICK THOMSON

de BROGLIE

RUTHERFORD

Bellringer

When scientists wanted to find out what an atom was, they were not able to look directly at what the atom was made of. They had to make inferences from the results of many different experiments. It was like trying to describe a picture, such as the one on the next slide, with only small portions visible.

Bellringer, continued

1. Write four sentences describing what you can see of the above picture.

2. What information or parts of the picture would make your descriptions more accurate without revealing the entire picture?

The Beginnings of Atomic Theory

〉Who came up with the first theory of atoms?.

Democritus• 1st to “think” of atoms• Derived from Greek

word – “unable to be divided” (indivisible)

• Called them - atomos• 4th century BC

Democritus did not have evidence for his atomic theory.

John Dalton• 1808• Atoms are tiny hard

spheres• Created the atomic

theory.– All atoms of a given

element are alike– Atoms of elements

could join to form compounds

Educated himself

age 12 became a school teacher

Dalton’s Atomic Theory, continued

• Dalton used experimental evidence.– Law of definite proportions: A chemical compound

always contains the same elements in exactly the same proportions by weight or mass.

Dalton’s theory did not fit all observations.

400 BC Democritus

1808 John Dalton:

1869 D. Mendeleev: organizes periodic table

1897 JJ Thompson

1911 Ernest Rutherford

1913 Niels Bohr

1923 Louis de Broglie

1932 James Chadwick

Atomic Theory through Time

Because of Mendeleev!!!

In 1898 …

W. Ramsay and M. Traves find Krypton, Neon and Xenon within 3 months using periodic table

• 1700s = indirect evidence of atoms

• 1st real proof atom’s existed (1905) Einstein calculations of Brownian motion, heat as atomic motion and momentum conservation.

•

400 BC Democritus

1808 John Dalton:

1869 D. Mendeleev: organizes periodic table

1897 JJ Thompson

1911 Ernest Rutherford

1913 Niels Bohr

1923 Louis de Broglie

1932 James Chadwick

Atomic Theory through Time

JJ Thomson• experimented with currents

of electricity inside empty glass tubes.

• PLAY THE SEGMENT FROM THE CD

JJ Thomson• experimented with currents

of electricity inside empty glass tubes.

• Discovered– electron in every atom– electrons have a negative charge– “Plum-pudding” model

Geiger and Marsden Ernest Rutherford

Lab 18.1 – Gold Foil Experiment

PLAY THE SEGMENT FROM THE CD

• particles – most passed straight through

• Atom mostly empty space !– some scattered at large angles

• Center positively charged nucleus

Rutherford

Niels BohrElectrons in an atom move in

a set path around the nucleus / similar to planets around the sun

Electrons orbit the nucleus

in fixed orbits

Orbits have fixed amount of energy

Louis de Broglie

• By 1925 Bohr’s Model was altered.– Electrons behave more like waves on– a vibrating string– analyzed a moving particle

as a wave

James Chadwick

• Research focused on radioactivity.• With Rutherford – knew there had to be

another particle with the proton in the nucleus (missing mass)

• discovered neutron • neutrons are the missing mass

in the atom

Atom • 1955• Mueller – Professor at Penn State• 1st to see an atom with an ion

microscope• synthetic Metals (???)

Atoms broken down further• Nucleus – Center of atom: Dense

– Protons and Neutrons: similar in size and mass• Protons – positive charge• Neutrons – no electric charge

• Outside the Nucleus– Electrons – cloud of tiny particles with little mass

• Electrons – negative charge (-1)

• Size – nucleus : marble – distance to electrons : stadium

Relative Size of Atoms

• Atom : Person as

Person : Ave. Star

• Atom : Apple as

Apple : Earth

(picture apple full of atoms and then Earth full of apples)

Who stated that elements are made of atoms?

Dal

ton

Chad

wic

k

Ruth

erfo

rd

Bohr

Thom

son

0% 0% 0%0%0%

1. Dalton

2. Chadwick

3. Rutherford

4. Bohr

5. Thomson

Who discovered the electron?

Dal

ton

Chad

wic

k

Ruth

erfo

rd

Bohr

Thom

son

0% 0% 0%0%0%

1. Dalton

2. Chadwick

3. Rutherford

4. Bohr

5. Thomson

Who discovered that atoms are mostly empty space?

Dal

ton

Chad

wic

k

Ruth

erfo

rd

Bohr

Thom

son

0% 0% 0%0%0%

1. Dalton

2. Chadwick

3. Rutherford

4. Bohr

5. Thomson

Who discovered the nucleus?

Dal

ton

Chad

wic

k

Ruth

erfo

rd

Bohr

Thom

son

0% 0% 0%0%0%

1. Dalton

2. Chadwick

3. Rutherford

4. Bohr

5. Thomson

Who discovered the proton in the nucleus?

Dal

ton

Chad

wic

k

Ruth

erfo

rd

Bohr

Thom

son

0% 0% 0%0%0%

1. Dalton

2. Chadwick

3. Rutherford

4. Bohr

5. Thomson

Who discovered the neutron?

Dal

ton

Chad

wic

k

Ruth

erfo

rd

Bohr

Thom

son

0% 0% 0%0%0%

1. Dalton

2. Chadwick

3. Rutherford

4. Bohr

5. Thomson

Who stated that electrons are located in fixed energy levels?

Dal

ton

Chad

wic

k

Ruth

erfo

rd

Bohr

Thom

son

0% 0% 0%0%0%

1. Dalton

2. Chadwick

3. Rutherford

4. Bohr

5. Thomson

Number VS Mass

• Atomic Number– # of protons in an atom

• Atomic Mass– # of protons and

neutrons

C12

6

Mass Number(# protons + # neutrons)

Atomic Number(# protons)

Chemical Symbol

Mass # - Atomic # = neutron #

12 – 6 = 6 neutrons

C14

6

How many protons?

How many electrons?

How many neutrons?

Draw a atomic model for this element?

Li 7

3

How many protons?

How many electrons?

How many neutrons?

Draw a atomic model for this element?

N 14

How many protons?

How many electrons?

How many neutrons?

Draw a atomic model for this element?

U238

How many protons?

How many neutrons?

Boron-11atomic number?

1 2 3 4 5 6 11

0% 0% 0% 0%0%0%0%

1. 1

2. 2

3. 3

4. 4

5. 5

6. 6

7. 11

Boron-11number of protons?

1 2 3 4 5 6 11

0% 0% 0% 0%0%0%0%

1. 1

2. 2

3. 3

4. 4

5. 5

6. 6

7. 11

Boron-11number of electrons?

1 2 3 4 5 6 11

0% 0% 0% 0%0%0%0%

1. 1

2. 2

3. 3

4. 4

5. 5

6. 6

7. 11

Boron-11number of neutrons?

1 2 3 4 5 6 11

0% 0% 0% 0%0%0%0%

1. 1

2. 2

3. 3

4. 4

5. 5

6. 6

7. 11

Boron-11number of energy levels?

1 2 3 4 5 6 11

0% 0% 0% 0%0%0%0%

1. 1

2. 2

3. 3

4. 4

5. 5

6. 6

7. 11

Boron-11valence electrons?

1 2 3 4 5 6 11

0% 0% 0% 0%0%0%0%

1. 1

2. 2

3. 3

4. 4

5. 5

6. 6

7. 11

Boron-11number of electrons in the first

energy level?

1 2 3 4 5 6 11

0% 0% 0% 0%0%0%0%

1. 1

2. 2

3. 3

4. 4

5. 5

6. 6

7. 11

ELECTRONS• Charge: –1 • Exact position can not be identified (cloud)• Found in Orbitals within Energy Levels

- 1st orbital: 2 (1s)- 2nd orbital: 8 (2s / 6p)- 3rd orbital: 8 (2s / 6p ) - 4th orbital: 18 (2s / 6p / (*3rd -10d)

- 5th orbital: 18 (2s / 6p / (*4th -10d)

Complete the energy levels …

• # of Protons?• # electrons?

• # e’ in 1st orbital?• # e; in 2nd orbital?• # of valence e’ ?

NITROGEN7

7

2

5

5

Electrons / Energy Levels

- closest to nucleus / lowest energy

As electrons FALL BACK to a lower energy level – ENERGY is given off.

Some energy levels can overlap – subdivided into orbitals

• Imagine floor is magnetic and shoes repel. Paper could pass under shoes….

• Sub microscopic world operates this way only it is ELECTRIC, not magnetic!

• Special Cases: nucleus of two atoms touch= thermal nuclear reaction.

FISSION / FUSION

ISOTOPES• Result when neutrons are added to an atom

• Vary in mass but are the same element because proton # is not changed

Atomic Mass Unit

• AMU– Is equal to 1/12th of the mass of a carbon

atom– 1 AMU = isotope of carbon ( 6 protons / 6

neutrons)

• Average atomic mass – weighted avg.

Center of a atom, contains most of the atom’s mass

Pro

ton

Neu

tron

Ele

ctro

n

Nucl

eus

Ener

gy le

vels

Mas

s num

ber

Ele

ctro

mag

neti.

..

0% 0% 0% 0%0%0%0%

1. Proton

2. Neutron

3. Electron

4. Nucleus

5. Energy levels

6. Mass number

7. Electromagnetic force

Positively charged particle that exists in the nucleus

of an atom.

Pro

ton

Neu

tron

Ele

ctro

n

Nucl

eus

Ener

gy le

vels

Mas

s num

ber

Eel

ctro

mag

neti.

..

0% 0% 0% 0%0%0%0%

1. Proton

2. Neutron

3. Electron

4. Nucleus

5. Energy levels

6. Mass number

7. Eelctromagnetic force

The least massive of the three subatomic particles which also carries an negative net charge.

Pro

ton

Neu

tron

Ele

ctro

n

Nucl

eus

Ener

gy le

vels

Mas

s num

ber

Ele

ctro

mag

neti.

..

0% 0% 0% 0%0%0%0%

1. Proton

2. Neutron

3. Electron

4. Nucleus

5. Energy levels

6. Mass number

7. Electromagnetic force

Particle with no charge that exists in the nucleus of an atom

Pro

ton

Neu

tron

Ele

ctro

n

Nucl

eus

Ener

gy le

vels

Mas

s num

ber

Ele

ctro

mag

neti.

..

0% 0% 0% 0%0%0%0%

1. Proton

2. Neutron

3. Electron

4. Nucleus

5. Energy levels

6. Mass number

7. Electromagnetic force

Describes how electrons are arranged around an atom

Pro

ton

Neu

tron

Ele

ctro

n

Nucl

eus

Ener

gy le

vels

Mas

s num

ber

Ele

ctro

mag

neti.

..

0% 0% 0% 0%0%0%0%

1. Proton

2. Neutron

3. Electron

4. Nucleus

5. Energy levels

6. Mass number

7. Electromagnetic force

The force that holds the atom together is called

Pro

ton

Neu

tron

Ele

ctro

n

Nucl

eus

Ener

gy le

vels

Mas

s num

ber

Ele

ctro

mag

netic

forc

e

0% 0% 0% 0%0%0%0%

1. Proton

2. Neutron

3. Electron

4. Nucleus

5. Energy levels

6. Mass number

7. Electromagnetic force

The total number of protons and neutrons in the nucleus of an

atom

Pro

ton

Neu

tron

Ele

ctro

n

Nucl

eus

Ener

gy le

vels

Mas

s num

ber

Ele

ctro

mag

neti.

..

0% 0% 0% 0%0%0%0%

1. Proton

2. Neutron

3. Electron

4. Nucleus

5. Energy levels

6. Mass number

7. Electromagnetic force

Fireworks• Heat added puts electrons at a higher energy level – coming down emits light.

• Different elements burn different colors because light is emitted a different wave frequencies

18.3 Periodic Table

PERIODIC TABLE• Groups similar elements together

– Arranged by the # of protons– Helps predict properties of an element

PERIODIC LAW – states that when elements are arranged in order by # of protons, similarities in properties will occur in a pattern

Today’s Element List

• 50 commonly used • 10 = 99% of the mass

of the Earth (5=92%)

(O,Si,H, Al, Fe, Ca,Na,Mg, Cl,K)

Atom Building Reminders

Symbol

PERIOD

GROUPS

To keep table shorter/ in line

GROUPS • Atoms of elements in the same group have the same # of valence electrons and therefore behave similarly

PERIODS • All elements in a period have the same # of atomic orbitals.

• Every element in period 1 has one orbital filled

FAMILIES OF ELEMENTS

• Metals– Shiny – Solids– Stretched and Shaped– Conductors of heat and electricity

• Nonmetals– Solids, liquids or gases– Solids – dull and brittle– Poor conductors of heat and electricity

• Semiconductors / Metalloids

METALS• 4 Different kinds of metals

– Alkali metals: soft, shiny and very reactive • Group 1: not found in nature as elements

– Alkaline earth-metals: less reactive• Group 2: have two valence electrons

– Transition Metals: many uses• Groups 3-12

– Synthetic Metals (???)

The Atom – Atom Building Game

Key Questions

• What are atoms and how are they put together?

• What does atomic structure have to do with the periodic table?

Subatomic Particles

• What three basic particles make up all atoms?

Subatomic Particles

• Protons• Neutrons• Electrons

Subatomic Particles

• The marbles represent these particles. Can you guess which marble represents which particle?

Subatomic Particles

•Protons•Neutrons• Electrons

Build a Carbon –13 atom

• Protons= carbon’s atomic #

• Neutrons = 13 – 6 = 7• Electrons = carbon’s atomic number

when electrically neutral

If you add a proton (+) and an electron (-) , what

element/isotope do you have?

• Protons = 7 (tells what the element is)

• Neutrons = 7 still• (tells what the isotope is) • Electrons = 7 (electrically neutral

when same # as protons … or it is an ion {charged})

• 4 players or teams per board• Each player starts with 6

blues, 5 reds, and 5 yellows in their board pocket.

• Each player takes turns adding marbles to the atom (up to 5 per turn) to make real, stable atoms.

• The first player to lose all their marbles wins!!!

The game of Atomic Challenge

• 4 players or teams per board• Each player starts with 6

blues, 5 reds, and 5 yellows in their board pocket.

• Each player takes turns adding marbles to the atom (up to 5 per turn) to make real, stable atoms.

• The first player to lose all their marbles wins!!!

Alkali MetalAlkali

EarthMetalMetalloids

Halogen Noble GasNon

Metal

Rare Earth Other-Metal Transition Metal

Orange Light Blue Circle Them

Dark Blue

Green

Dark Orange REDYellow

PurpleRoyal Blue

Noble Gases

RED

YELLOW