Starter: Quick Review• How many minutes are in 2 weeks?• Express the answer to 10.5m + 12.15m in

correct sig figs• Express 525K in degrees Celcius• The mass of a sample of salt is 20kg. The

density of the salt is 4g/cm3. What is the volume of the sample of salt in mL?

As you come in,

The Materials:• Paper and pencil for notes• ½ sheet of paper• History timeline• Pick up packet.The Plan:• Discuss your Unit One tests (return ASAP)• Learn about basic atomic structureHomework:• Complete the Atomic Structure Numbers

WorksheetNOTE: Models of the Atom, Isotopes, Atomic Mass &, Atomic Structure Numbers Quiz on Monday

Starter: Let’s Jog Your Memory

• So…what is an atom?• Draw a diagram of an atom

labeling the following parts: nucleus, electron cloud, proton, electron, neutron

• Describe the 3 subatomic particles (Ex: location, charge, mass, etc)

Back to the Reading• Who theorized that all matter is composed of fire, air,

water, and earth?• Name the famous Greek philosopher who agreed

with the theory described above.• Name the scientist who established the Law of

Conservation of Matter. • Name the famous Greek philosopher who disagreed

with #1 and said that matter could be broken down into “atomos.”

• Who said that “All atoms of a given element are identical.”?

Atomic Theory• History of the Theory:

– Early ideas of the atom• Democritus• Aristotle• John Dalton (pg. 56)

Atomic Theory• History of the Theory:

– Early ideas of the atom• Democritus - “atomos”; atoms exist• Aristotle - atoms do NOT exist• John Dalton (pg. 56) - 2000 years later; atoms

exist– Matter is made up of atoms.– Atoms are indivisible.– Atoms of same (different ) elements are same

(different)– LAW OF CONSERVATION OF MATTER

More Recent Atomic Theory• E. RutherfordNucleus in gold foil

experiment

(Protons travel in different directions when they hit the nucleus)

• JJ ThomsonFound Electrons through the cathode ray experiment

Modern Atomic Theory• Neils BohrFirst atomic model to

show Energy levels

• SchrodingerSublevels & orbitals

Subatomic ParticlesParticle Location Charge Actual Mass Relative

Mass

Proton Nucleus +1 1.673x10-24 1

Neutron Nucleus None 1.675x10-24 1

Electron Electron Cloud (in energy levels)

-1 9.11x10-28 1 1840

Proton Significance• Gives the atom its identity• Equivalent to the atomic number• Massive particle so adds to the atom’s

mass• Gives the nucleus its positive charge• Balances the negative charge of the

electrons

Neutron Significance• Neutron glue that holds the nucleus

together• Massive particle so adds to the atom’s

mass (mass number= p + n)• Number can differ from one atom to

another giving isotopes

Electron Significance• Responsible for chemical properties• Forms ions when gained or lost, which

leads to a charge

Atomic NumberThe picture is NOT completely correct.

• Atomic # IS the number of protons in the atom. It is NOT always the number of electrons.

• Therefore, the atomic # gives the atom its identity...its name.

Atomic Number• In isotopic notation, the atomic number

is shown in the lower left corner of the element symbol.

• Example:

6C

Atomic Number- Quick Check

• If an atom is found to have 28 protons, what is its identity?

• What is the atomic number of phosphorus?

• How many protons does barium have?• Show the following elements in “isotopic

notation”:– Lithium, sodium, sulfur, lead

Atomic Number- Quick Check

• If an atom is found to have 28 protons, what is its identity? Ni = Nickel

• What is the atomic number of phosphorus? 15

• How many protons does barium have? 56

• Show the following elements in “isotopic notation”:– Lithium, sodium, sulfur, lead

Charge• Charge = oxidation state

– Oxidation state is just a fancier way to say it.

• A charged atom results from an inequality between protons and electrons in an atom.

• Which of those particles (protons or electrons) are more likely to be gained or lost from an atom? Why?

Charge Example• Example: Bromine has 35 protons. It

often gains electrons to other atoms. If Bromine gains an electron, the atom will have 36 electrons. What will the charge be?– Answer: -1 charge

Charge...Now , you try• Example: Calcium has 20 protons. It

often loses electrons to other atoms. If calcium loses 2 electrons, the atom will have only 18 electrons. What will the charge be?– Answer: +2 charge

Charge• In symbolic notation, the charge is listed

in the top right corner of the element symbol. If the charge is neutral, then the corner is left blank.– Question: What does Cl-1 means for the

amount of protons and electrons for a chlorine atom?

– Answer: protons = 17 (don’t change), electrons = 18 (gained one)

ChargeQuick Check

• What is the charge of sulfur when it gains 2 electrons to the neutral atom?

• Write the symbolic notation to represent an atom of aluminum that has lost 3 electrons leaving 13 protons and 10 electrons.

• How many protons and electrons are in the following atom? Cu 2+

ChargeQuick Check

• What is the charge of sulfur when it gains 2 electrons to the neutral atom? S-2

• Write the symbolic notation to represent an atom of aluminum that has lost 3 electrons leaving 13 protons and 10 electrons. Al3+

• How many protons and electrons are in the following atom? Cu 2+ 29P, 27E

Mass Number

• Consider the subatomic particles. Which TWO particles have enough mass to matter?

• Mass number is always a whole number...no decimals.

• Mass number is calculated by adding the number of protons to the number of neutrons.

Mass Number• In symbolic notation, the mass number

is shown in the upper left corner of the element symbol.

• Example:12

6C

**Important Equations**

Mass NumberQuick Check

• If a sodium atom has 11 protons and 12 neutrons, what is the atom’s mass number?

• How many neutrons does a copper atom with a mass number of 64 have?

• How many protons and neutrons are in the atom represented with this symbolic notation: 32

16S

Isotopic Notation Summary• Shorthand way to record the element symbol,

atomic number, charge, and mass number.• With this information, you can deduce the

number of protons, neutrons, and electrons in the atom being represented.

XMass #

Atomic #

Charge

Starter: Atomic Structure• Isotopes of the same

element have different numbers of _________ in their atom but the same number of _______.

• ________ do not affect the atom’s mass but determine the oxidation state.

• How many protons, electrons and neutrons are in the following atom?

58 Cerium-140

Write the correct isotopic notation for the element that has 26 protons, 30 neutrons, and 23 electrons.

Take 10…Finish Up• Complete at least 4

stations in the gallery walk

• Isotopic Notation must be complete (atomic #, atomic number)

• The assignment will be turned in for a grade today

• If you finish early, take out your Unit 2 review packet that you received yesterday and work on the Atomic Number WS

• Please ask if you have any questions

Atomic Structure: Part II• Students will understand…

1. The difference between mass number and atomic mass

2. How to calculate average atomic mass and relative abundance

Blocks on the Table

• PROTONS give an atom its identity. They are the ONLY subatomic particle that must be identical from one atom to another. Neutrons AND electrons can vary...

• SO, how can we create ONE box on the periodic table to represent ALL atoms of an element? We must represent AVERAGE atoms. (That’s why the atomic mass has decimals.)

Atomic Mass• Atomic mass = the weighted average of

all of the types of atoms (isotopes) of the element– Must know the % abundance (how much of

it is found in nature relative to other isotopes) and the mass number

– Check out the example!

Atomic Mass Example• Copper exists as a mixture of 2 types of

atoms. The lighter copper has 29 protons and 34 neutrons, and it makes up 69.17% of all copper atoms. The heavier type has 29 protons and 36 neutrons. It makes up the remaining 30.83% of copper on earth. What is the atomic mass of copper?

Atomic Mass Example• Element Z exists in 3 isotopic forms.

The isotopic mixture consists of 15% Z-16, 35% Z-17, and Z-18 makes up the remaining percent. What is the atomic mass of this element?

Relative Abundance Calculation

• Element X has two naturally-occurring isotopes with isotopic weights of 10 and 12. You look on the periodic table to find that its average atomic mass = 10.5 What is th relative and percentage abundance of each isotopes?

Relative Abundance Calculation

• Silver has two naturally-occurring isotopes with isotopic weights of 106.90509 and 108.90470. What is the relative and percentage abundance of each isotopes?

Starter: AM Review• Element M exists in 3 isotopic forms. The

isotopic mixture consists of 20% M-10, 50% M-15, and M-20 makes up the remaining percent. What is the atomic mass of this element?

• Chlorine has two isotopes. Chlorine-35 has an exact weight 34.968852 amu, and it has a 75.77% abundance. The other isotope has 36.965903 amu. What is the atomic mass?

Isotope/Atomic Mass Lab– You and your partner will analyze a sample

of the element Candium. – Gather the data, and calculate the atomic

mass of candium.– You can eat your sample at the end! 8-)– Work on the new atomic mass calculations

ws at your desk when you are done.

Isotope/Atomic Mass Lab– Important Information:You can write on the sheet providedBe sure to keep correct sig figs after

measuring the massKeep your candy on a paper towel if you

plan to eat themStraighten up your lab area when you are

finishedBe sure to stay on task…the assignment is

graded!

Starter• Hydrogen has two naturally-occurring

isotopes with isotopic weights of 1.007825 and 2.014102. What is the relative and percentage abundance of each isotope?

• True or False: - Isotopes of an atom have different

numbers of protons.- Although atoms are mostly empty space,

they still have mass.

Energetic Electron• Electrons are energetic, and they exist on

energy levels.• Quantum: specific amount of energy needed

to move from one energy level to the next; energy levels are given principal quantum numbers as a result

• When electrons change energy levels, energy is absorbed and released.

• Light is sometimes visible when the energy is released (Emission of Light)

Quantum Illustration

Quantum = distance between two energy levels

Principal Quantum Number (n) = begin counting closest to the nucleus

Quantum Illustration

Principal Quantum number (n):- Refers to the principal

energy level, which tells you the amount of energy the electron has

- The CLOSER the electron is to the NUCLEUS the LESS energy it has

Quantum Leap Illustration1. An electron from n=2

(ground state) can absorb a quantum of energy and jump to n=3 (excited state).

2. Excited state is temporary.3. The electron will soon

release the quantum and fall back from the higher level to ground state.

4. EMISSION OF LIGHT can occur and the released energy will travel as a wave.

Electromagnetic Spectrum(All energy waves fall into one of these

categories.)

Electromagnetic SpectrumLet’s see if you get it…wavelength vs frequency

Calculating the Emission of Energy

• Two Equations to calculate the energy:1. Speed of light = wavelength x frequency

c = λν c = 3.0 x108 m/s (speed of light is constant)

2. Energy = Planck’s constant x frequency

E = hν h=6.626x10-34 Jsec (Planck’s constant)

Look at the two equations. What variable do they have in common?

A.) Speed of light (c)

B.) Wavelength (lambda)

C.) Frequency (nu)

D.) Energy (E)

Finding a Connection

Electromagnetic Wave Calculations

• So, if I know the _______ of a wave, then I can calculate its wavelength AND its energy.

Energy Practice Problem:

If the wavelength is 0.001 meters, then what is the frequency of the wave?

A.) 300,000 Hz

B.) 3.0x1011 Hz

C.) 3.33x10-12 Hz

D.) 6.626x10-37 Hz

Energy Practice Problem:

If the wavelength is 0.001 meters, then what is the energy of the wave?

A.) 1.99x10-22 J

B.) 2.21x10-45 J

C.) 1.99x1046 J

D.) 6.626x10-37 J

Energy Practice Problem:

If the frequency is 7.0x1013 Hz, what is the wavelength of the wave? What is

the energy of the wave?

A.) 4.29x106 m; 4.63x1020 J

B.) 2.33x105 m; 1.55x10-28 J

C.) 4.29x10-6 m; 4.63x10-20 J

D.) None of these

Starter:• When do electrons emit light?• If an electron moves farther from the

nucleus what happens to its energy?• If the frequency is 4.0x1012 Hz, what is

the wavelength of the wave? What is the energy of the wave?

Electron Configuration• Electrons are arranged into different

levels within the electron cloud based on their energy

• In order to arrange the electrons, you must first know how many there are

Hoya Hotel…The analogy• Hotel = electron cloud• Floors = principal energy levels

–1-7 COEFFICIENTS• Rooms = sublevels (consist of

orbitals)–s = sphere, p = dumbbell, d & f

• Guests = electrons–Up and down = direction of spin

Hoya HotelRooms (Sublevels) available:

S: Single room, has only one bed (sleeps 2)

P: Prestige room, has three beds (sleeps 6)

D: Deluxe room, has five beds (sleeps 10)

F: Fabulous room, has 7 beds (sleeps 14)

So…how can I remember these levels

• The DIAGONAL RULE will help you to determine the order for placing the electrons into their sublevels

Lets practice…Write the electron configuration for the following

1. Oxygen 2. Bromine

Noble Gas Notation• Noble Gas Notation is a shorter way to

write out electron configurations• Start the configuration at the noble gas

just before the atom and complete the normal electron configuration

• Lets look at oxygen and bromine again…

Periodic Table Labeling

S block: blue d block: red

P block: yellow f block: green

Periodic Table Labeling

S block: blue d block: red

P block: yellow f block: green

What does this all mean?• Let’s analyze the configuration of magnesium.

– Energy levels– Sublevels– Electrons– Valence level and electrons

• What can I NOT find represented in the electron configuration?– Orbitals– Pairing

Hoya Hotel• Terms of Occupation:

– Aufbau Principle: Each room/bed on the lower floors must be occupied before moving to a higher floor.

– Pauli Exclusion: A maximum of two guests may occupy a bed. Guests must sleep head to foot.

– Hund’s Rule: Single guests must occupy separate beds in a room. No pairing occurs unless no empty beds exist.

Orbital Diagrams• Visual representation of electron cloud• Shows everything that electron configuration

shows PLUS orbitals & pairing– How to Draw an Orbital Diagram

• Write the electron configuration first.• Draw the “beds” (orbitals) under each room.• Put the electrons in the “beds.”

Let’s practice...• Write the electron configuration for:

– Fluorine– Magnesium– Palladium

• Write the noble gas notation and orbital diagrams for the elements above.

Starter:• Write the correct electron configuration,

noble gas notation, and orbital diagram for Barium

Which of the rules for filling orbitals does the picture to the right of the board violate?

Flame Test Lab Instructions• You will rotate between the stations from

1 to 6• Dip the wire into the solution and place

in the fire. Observe the color.• In your data table, write a detailed

description of each color you see• These descriptions will help you to

determine your unknown

Analyzing Orbital Diagrams & Stability of Atoms

• Electrons are responsible for the chemical properties (personalities) of atoms.– STABLE = All orbitals (beds) are full.– PRETTY STABLE = All orbitals (beds) are full

OR half-full.– UNSTABLE = Empty orbitals (beds) exist.

NOTE: If an atom has to have an empty orbital, it is best for the empty orbital to be on the valence energy level so that it might be filled by electrons from a nearby atom.

Draw the orbital diagram of sodium. Is sodium stable, pretty stable, or unstable?

A.) Stable

B.) Pretty Stable

C.) Unstable

Analyzing Stability

Draw the orbital diagram of chromium. Is Cr stable, pretty stable, or unstable?

A.) Stable

B.) Pretty Stable

C.) Unstable

Analyzing Stability

Practice Analyzing Stability1. Draw the orbital diagram of sodium. Is

sodium stable, pretty stable, or unstable?– Answer: UNSTABLE; Sodium has one half-full

orbital, but it’s third energy level has three empty p orbitals.

2. Draw the orbital diagram of chromium. Is Cr stable, pretty stable, or unstable?

– Answer: UNSTABLE; chromium has one empty orbital.

Exceptions to the Rules• Exceptions to Aufbau principle:

– Chromium and Copper columns ONLY– Stability of filled and half-filled sublevels

• Arrangement’s impact on bonding

Atomic Emission Spectra• Unique to each element• “Fingerprint”• Used to identify unknowns• Shows all wavelengths of visible light

given off by an atom• Flame Test Lab

Starter:• Write the correct electron configuration,

noble gas notation, and orbital diagram for the following atoms:

1. Calcium 2. Silver

True or False: Emission of light occurs when an electron absorbs energy and jumps from the ground state to a higher level.