Warm Up1. What is matter? 2. What does a

“particle” look like?3. Why did Apple create

the Iphone 4 when they already created the original Iphone?

EQ: How has our model of the atom changed over time?

• HOT Q1: Did you make a Beast Mode on the test? If not, what are you going to do for the next test?

• HOT Q2: How did Democritus envision “the atom”?

• HOT Q3: What is our understanding of the atom today?

Agenda• Warm Up/Objective• Test Return / Tracking• Scientists: Videos • Video: Atomic Structure• Atomic Structure• Exit Ticket

Test Return / Tracking

• Averages:– 1st Block: 76.9%– 2nd Block: 92.1%– 3rd Block: 79.0%

No Excuses

• http://www.youtube.com/watch?v=obdd31Q9PqA

This is what your test looked like…

• http://www.youtube.com/watch?v=1XrzTgvBd6Q

Let’s reflect…1) For my Unit 3 test, I earned ____%. • When I received my graded test, I felt

_________because_____________________. • I think I received this score because• To prepare for this test, I did the following

things:

Intro to the Atom

• http://www.teachertube.com/viewVideo.php?video_id=105573

• Take a pile of paper clips• Divide the pile into two equal piles.• Divide each of the smaller piles into two

equal piles.• Repeat step 3 until you are down to a pile

containing only one paper clip. That one paper clip still does the job of a paper clip (i.e., hold loose papers together).

• Cut that one paper clip in half. Can half of the paper clip do the same job as the single paper clip?

Let’s Take a Trip Through Time!

Notes: Historical Model of the Atom

In our TOC…Unit 4: The AtomNotes: Historical Model of the Atom, p.___

On the next clean page of your notebook…Notes: Historical Model of the Atom Date

THOMPSON

Sequence

• Democritus• Dalton• Thompson• Rutherford• Bohr• Schrödinger/Heisenberg

Democritus460 – 370 B.C.

• First model of an atom!

Pick a Candy!

John Dalton1766-1844

• A given compound always has the same relative numbers and kinds of atoms

Dalton’s Model

Pick a Candy !

Pick a Candy!

J.J. Thomson1856-1940

• Discovered electron – Cathode Ray Experiment

• Plum Pudding model 1904– Electrons in a soup of positive

charges

Video: http://videos.howstuffworks.com/science-channel/29292-100-greatest-discoveries-the-cathode-ray-tube-video.htm

JJ Thomson’s Ideas

Plum Pudding Model

Pick a Candy!

Pick a Candy!

Ernest Rutherford1871-1937

• Nucleus Theory 1910– alpha particle gold foil

experiment

• An atom’s mass is mostly in the nucleus

• The nucleus has a positive charge (Moseley)

• Electrons in fixed orbit

Rutherford

Video: http://player.discoveryeducation.com/index.cfm?guidAssetId=C313E1E3-D880-4896-B29E-F0815F2E0A61&blnFromSearch=1&productcode=US

Alpha Particle Experiment

Rutherford Model

Pick a Candy!

Pick a Candy!

Niels Bohr1885-1962

• Planetary Model 1913– Nucleus surrounded

by orbiting electrons at different energy levels

– Electrons have definite orbits

• “Thought” experiment

Bohr’s Model

Pick a Candy!

Ernst Schrödinger 1887-1961

• Quantum Mechanical Model 1926– Electrons are in probability

zones called “orbitals”, not orbits and the location cannot be pinpointed

– Electrons are particles and waves at the same time

– Developed quantum numbers based on theories of Einstein and Planck

Werner Heisenberg 1901-1976

Orbitals

Pick a Candy!

400 BC 1803 1904 1910 1913 1926

Niels Bohr

J J Thomson

Democratus

John Dalton

Schroedinger / Heisenberg

Ernest Rutherford

Atomic Theory

Exit Ticket1. Experiments with the cathode-ray tube demonstrated that

a. atoms are positively chargedb. visible light was influenced by a magnetc. a cathode beam consists of negatively charged particles d. atoms contain a nucleus

2. Why did most of the alpha particles go straight through the gold foil in Rutherford’s experiment?

a. Most of an atom is empty space.b. Alpha particles are positively charged.c. Alpha particles move with high velocity.d. The center of an atom is positively charged.

Atomic Structure

Warm Up1. To the best of your

knowledge, what are the parts of an atom? Draw a picture if you like.

2. What are some spherical objects that have centers which are different from the outside?

Essential QuestionsEQ: What is the structure

of an atom?HOT Q1: How does the

college credit system work?

HOT Q2: What are three subatomic particles?

HOW Q3: Are atoms neutral?

College Credits! • Midterm and final Exam (>85%, 10 credits)• Unit Exams (>85%, 5 credits)• Quiz mastery (>85%, 3 credits)• Attendance (2 credits for perfect attendance for

whole week)• Peer tutoring (1 credit for excellent peer tutoring)• Participation (1 credit for excellent participation

(question or comment) during class)• Classroom Leader Compensation (3 credits/week)• What else do you think should factor into system?

• Point breakdown– Honor society = 24 pts– Bachelors Degree= 48 pts– Masters Degree = 72 pts– Doctor of Philosophy in Science= 96 pts

Classroom Leadership Positions

Classroom Leadership Positions

Classroom Leadership Positions

Classroom Leadership Positions

**Please note, other positions may be added at a later date. If you do not see a position that suits you, you may suggest a position. If you suggest a position, please offer a clear job description.

**If you are selected for a position, you will be required to sign a contract. You will also be given a more detailed description of your duties and responsibilities.

Application Process

• Fill out application and return to me Monday, October 3rd

• I will be making decision regarding classroom leadership positions by Wednesday, October 5th

Video: Atomic Structurehttp://player.discoveryeducation.com/

index.cfm?guidAssetId=f6b8c2bb-fb87-472d-82d0-f9d21de42161&blnFromSearch=1&productcode=HUB

Video Summary:

Consensus

Amu = atomic mass unit

PToE

• DO NOT LOSE THIS!!!

Atomic Number The number of protons “defines” the element. For example:

The number of protons in an atom is known as the atomic number.

It is the smaller of the two numbers shown in most periodic tables.

hydrogen atoms always contain 1 proton

carbon atoms always contain 6 protons

More about atomic number

Changes in the number of particles in the nucleus (protons or neutrons) are very rare. They only take place in nuclear processes such as: radioactive decay

nuclear bombs

nuclear reactors.

If the number of protons changes, then the atom becomes a different element.

• Ordinary atoms are NEUTRAL. They have the same number of PROTONS and ELECTRONS thus, the positive and negative charges are EQUAL, so they cancel each other out

What is the atomic number?

tin

iron

sodium

fluorine

What is atomic mass?Electrons have a mass of almost zero, which means that the mass of each atom results almost entirely from the number of protons and neutrons in the nucleus.

The sum of the protons and neutrons in an atom’s nucleus is the atomic mass.

Atomic mass = number of protons + number of neutrons

Element Protons Neutrons Atomic Mass

Helium 2 2

Fluorine 9 10

number of neutrons = atomic mass - number of protons

How many neutrons?

How many neutrons are there in these atoms?

Element Protons Neutrons Atomic Mass

Strontium 38 88

Zirconium 40 91

Who I am I?

I discovered the electron through the use of cathode rays.

Created the plum pudding model and thought (incorrectly) that electrons were in the center of an atom.

Who I am I?

I proposed that atoms can combine in fixed ratios to form new substances

Who Am I?

• I proved that electrons exist only in discrete energy states

Who I am I?

We found that electrons can behave both as a particle and as a wave

We found that you cannot pinpoint the exact location of an electron

Who I am I?

I discovered that most of the mass in an atom is concentrated in a dense, “nucleus” at the center of the atom.

I found this through the gold foil experiment.

Worksheet 4.1

• Fill it out. Fill it out. Fill it out.

Exit Ticket• How many protons and electrons are in a neutral

Magnesium atom? (use your Periodic Table)• Label each of the following parts

CC

AA BB