On the front table there is a stack of papers titled “Mercury: Mysterious and Deadly”.

Get one of these papersIt is an article that you will read silently

There are 7 questions you will answer by yourself on the back.

On your Bell Work for “Tuesday” you need to write “ARTICLE”

BELL WORK: TUESDAY 2/7/12

How did Mercury get the nickname “quicksilver”?What did alchemists struggle to make using mercury

and sulfur?Many people over time were found to have health

problems. What was eventually found to be the cause of it?

What type of effects happen to people surrounded by mercury? High School Chemistry Story

Why is vacuuming a mercury spill not the best way to clean up a mercury spill? Middle School Story

What does this article have to do with Chemistry?

Why would your teacher have you read an article like this?

MERCURY: MYSTERIOUS AND DEADLY QUESTIONS

…identify substances based on their physical and chemical properties

By the end of this unit, you will be able to…

…separate mixtures into their basic

components

…sort elements based on their

physical & chemical properties

…identify the bonds that hold atoms

together and describe properties

associated with these bonds

…describe how the elements are

arranged on the Periodic Table of

Elements

…describe the atom as the basic building block of matter

Questions to Consider:

What do you hope to accomplish throughout the upcoming Chemistry unit?

What goals do you have for the rest of the 2nd semester?

What long-term goals do you have for science?

SETTING GOALS

Atom- basic building block of all matterAll substances are made up of matter

Smallest particle of an element that has the properties of that element

5.1 - TSW explain that matter is composed of tiny particles called atoms.

WHAT IS AN ATOM?- PAGE 1

Nucleus- tiny, central core of an atomContains protons (positively-charged)Containing neutrons (with no/neutral charge)

Electrons move around the nucleus in electron cloud

STRUCTURE OF AN ATOM

Get a book off the front table and the pink packet.

Begin working on page 1 – the Nature of Science Vocab.

Be sure to have the definition of each word written down

You will only be given 10 minutes to work on this.

Whatever is not finished today will be done as homework.

BELLWORK: WEDNESDAY 2/8/12

Subatomic Particles- particles that make up an atomProton- positively charged; located in nucleus

Neutron- neutrally charged; located in nucleus

Electron- negatively charged; located outside of the nucleus; negligible mass (very small)Electrons revolve around nucleus in imaginary paths called orbits or shells

Valence electrons- electrons that are the farthest away from the nucleus (in the outside shell)

Electrons……move around the nucleus very

fast…have a HUGE space to move

around in…are different distances from

the nucleus…form a negatively charged

cloud around the nucleus…travel in paths called orbitals…cannot be exactly located at a

particular moment- probably do (probability) Imagine the blades of a moving fan…where are they exactly?

THE ROLE OF ELECTRONS

Fill in the picture on page 1 with the appropriate subatomic particle names, charges, and locations in the atom.

A B C DSubatomic

Particle Proton Neutron Electron Valence Electron

Charge Positive (+)

Neutral (0) Negative (-) Negative (-)

Location in atom

Inside nucleus

Inside nucleus

Outside nucleus

Outside nucleus; outer “valence”

shell

FILL IN THESE ON PAGE 1

A BC

D

Imagine standing at the pitcher’s mound in a baseball stadium.

If the nucleus were the size of a pencil eraser, the electrons could be in the outfield or the top row of seats!

LITTLE PARTICLES, BIG SPACES

Atomic Number- the unique number of protons in a nucleus

# of (+) protons = # of (-) electrons

Atoms are neutrally charged (not positive or negative)

Ex: Every Carbon atom has 6 protonsHow many electrons in a Carbon atom?

6 (# of (+) protons = # of (-) electrons)

ATOMIC NUMBER

Atomic Mass- the average mass of one atom of an element; protons + neutronsAtomic mass units (amu)- unit for measuring very small mass of subatomic particlesProton mass = 1 amuNeutron mass = 1 amuElectron mass = 1/2000 amu

~2000 electrons = 1 amuMost of an atom’s mass is in its nucleus

Gold, Au, has an atomic number of 79How many protons?

79How many electrons?

79Gold, Au, has an

atomic mass of 196.97How many neutrons?

196.97 – 79 = 117.97How many amu’s

79 + 117.97 = 196.97

CHECK YOUR UNDERSTANDING

At your party you need 10 pizzas to feed everyone. You buy 6 pizzas. How many pizzas must other people provide if you are going to have 10 total?The total # of pizzas is like the

atomic mass. Protons bring some of the mass, and neutrons bring the rest. Electrons don’t really bring anything!!!

Element- Substance made up of one kind of atomCannot be broken down into other substances by chemical and physical means

All listed in the Periodic Table ~82 naturally-occurring elements

~31 synthetically prepared (artificially-made) elements

WHAT IS AN ELEMENT?

Germanium

Sulfur

Mercury

“Element” = Carrot Imagine chopping a carrot

into smaller and smaller pieces.

You would eventually reach a point where you could not cut anymore because the pieces were so small.

But, those small pieces still have the properties of the larger carrot (taste, color, etc.).

Element = Aluminum Imagine cutting Aluminum

(Al) into smaller and smaller pieces.

When you can no longer divide it, they are Al atoms.

But, they still have the properties of Aluminum (shiny, silver color, fragile, thin, etc.)

When atoms bond together, they form:Molecule – a combination of 2 or more

of the same or different atoms that are bonded togetherEx: H2O, NaCl, H2, O2, O3, N2

Diatomic Molecule- made of two of the same atoms Hydrogen, Nitrogen, Fluorine, Oxygen, Iodine, Chlorine,

Bromine H2 O2 F2 Br2 I2 N2 Cl2

HOFBrINCl twins; I Have No Bright Or Clever Friends; Hydrogen; the rest form a 7 on the periodic table: N, O, F across, then going down Cl, Br, I

Compound – a molecule that contains atoms or molecules of two or more different elementsEx: H2O, C6H12O6, CH4

MOLECULES VS. COMPOUNDS

Fill in the following chart with the appropriate subatomic particle names, charges, and locations in the atom.

A B C DSubatomic

Particle Proton Neutron Electron Valence Electron

Charge Positive (+)

Neutral (0) Negative (-) Negative (-)

Location in atom

Inside nucleus

Inside nucleus

Outside nucleus

Outside nucleus; outer “valence”

shell

BELLWORK: THURSDAY

2/9/2012

A BC

DFill these in on

page 1

Hypothesis – an educated guess, based on observationTheory – summarizes a hypothesis or group of

hypotheses that have been supported with repeated testing. This answers the question of “why” This is valid as long as there is not evidence to dispute it.

Law – generalizes a body of observations. At the time it is made, no exceptions have been found. These explain things, but do not describe them. Does not answer “why”

For a theory to become a law it must… Not have any evidence to disprove it Have a hypothesis that has been testing many different ways

and times

WHAT IS A THEORY AND HOW DO YOU MAKE ONE?

Read the passages provided, and answer the questions about each scientist and their experiments.

EVOLUTION OF THE ATOMIC THEORYPGS 2 & 3

John Dalton1. Atomic Theory

of Matter2. Atoms3. Different4. Atoms of

different elements

5. 1:1

J.J. Thomson1. The electron2. Negative3. Negatively

charged electrons

4. Opposite charges attract each other

5. Gas discharge tubes

EVOLUTION OF THE ATOMIC THEORY- PG 3

Lord Ernest Rutherford1. Positive2. He was shooting alpha

particles through a gold foil sheet

3. Most particles passed straight through the foil.

4. Some got deflected back, others went through.

5. Positive repels positive (positive nucleus repels positive alpha particles)

Niels Bohr1. The electrons go

around the nucleus like planets around the sun.

2. They are in different energy levels; different distances from the nucleus

3. 32 electrons4. Higher level =

absorb/gain energy5. Release (lose)

EVOLUTION OF THE ATOMIC THEORY- PG 4

EVOLUTION OF THE ATOMIC MODEL

John Dalton(1802)

J.J. Thomso

n (1897)

Ernest Rutherford (1911)

Niels Bohr (1913)

Erwin Schrödinger & Louis de

Broglie (1920’s - present)

Who was he?A Greek philosopher

Discovery: Matter can be cut into small pieces

The smallest piece cannot be broken down anymore = an atom“Atomos” – Greek for uncuttable

Everything is composed of atomsAtoms are always in motion

Model: The atom is a small, solid sphere

DEMOCRITUS (~400 BC)

Who was he?British schoolteacher, meteorologist

Experiment: Studied the atmosphere and the behavior of gases; he found they always combined in predictable ways.

Discovery (1802): Each element is made up of atoms

Atoms of the same element are the same.

Atoms of different elements are different

“Billiard Ball Model” (Pool Ball):The atom is a small, solid sphere

JOHN DALTON (1802)

1. Where is the majority of an atom’s mass?

2. What subatomic particles compose the majority of an atom’s mass?

3. Tricky: What composes the majority of an atom’s volume?

4. Beryllium’s atomic number is 4, and its atomic mass is 9.01. How many protons, neutrons, and electrons are in one Beryllium atom?

1. Nucleus2. Protons & Neutrons3. Nothingness!

Empty space around the nucleus

99.9% of matter is actually empty space!

4. 4 protons, 5 neutrons, 4 electrons,

BELLWORK: FRIDAY 2/10/2012

EVOLUTION OF THE ATOMIC MODEL

John Dalton(1802)

J.J. Thomso

n (1897)

Ernest Rutherford (1911)

Niels Bohr (1913)

Erwin Schrödinger & Louis de

Broglie (1920’s - present)

Who was he?A British scientist

Experiment: Using a gas-discharge/cathode ray tube, he passed an electric current through a vacuum tube

Saw a stream of glowing material!!Discovered that mysterious glowing stream would bend toward a positively charged electric plate

The stream was made up of small particles that carried a negative charge--electrons.

J.J. THOMSON (1897)

Discovery (~1897):The negatively charged electron

2000 electrons = the mass of one proton

The “Plum-Pudding Model”: Atoms are spheres filled with a positively charged fluid; electrons are scattered throughout Fluid = “pudding”; electrons = “plums”

Who was he? New Zealand physicist

LORD ERNEST RUTHERFORD (1909-1911)

• Experiment: “The Gold-Foil Experiment”• Fired positively charged

particles (called alpha particles) at a thin sheet of gold foil

• Most particles went through, some bounced back, some were deflected

Discovery (1909-1911): Atom is mostly empty space Positively charged nucleus in the center of the atom positive repels positive

The “Planetary Model”: Dense, small, positively charged nucleus

Surrounded by freely moving electrons

Who is he? A Danish physicist

Experiment: Known:

Elements possess specific amounts of energyLight was given out when they were heated, but no one could explain why

Bohr looked at line spectra (colored lines of light), which show energy being emitted.

Energy was released when electrons moved from one shell to another

Bohr suggested the electrons must orbit nucleus in fixed energy levels (or electron shells)

NIELS BOHR (1913)

Discovery (1913): Electrons move in fixed orbits around the nucleus (electron shells)

Electrons exist in energy levelsAtoms absorb or give off energy when electrons move from one shell (energy level) to another

The “Bohr Model”:An electron's energy levels (also called electron shells) can be imagined as concentric circles around the nucleus

Who were they?Louis de Broglie was a French scientistErwin Schrodinger was a Austrian physicist

Experiment/Observation: It is impossible to know the speed and exact location of an electron

It is only possible to calculate the probability of finding an electron within a given space

ERWIN SCHRÖDINGER & LOUIS DE BROGLIE (1925 THROUGH PRESENT)

Discovery (~1925): Electrons travel in clouds

around the nucleus Electrons can behave like

waves or particlesThe “Electron Cloud

Model” or “Quantum Mechanical Model”: There are no defined orbits of

electrons around the nucleus, just areas where they “might” orbit

ATOMIC THEORY TIMELINE- RECAP