I wonder:

What is

Matter?

Name ____________________________

Teacher _______________Hour _______

IPS website: http://www.mononagrove.org/faculty/ips/index.cfm

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Unit Summary Content Based Goals

Learning Goal Activity(s) Observed

Big Ideas

Students can define the four element theory

-Alchemy presentation and notes

• The four element theory states that all matter can be broken down into four main substances:

1. earth 2. air 3. 4. water 5. fire

Students can explain the difference between science and pseudoscience

-Alchemy presentation and notes -Science vs. Pseudoscience activity

• Pseudoscience (def.): a practice that claims to be scientific but does not properly follow the scientific method.

• How to identify pseudoscience: (write in at least 2) o Does not fit the 3 criteria: PBS o Use of vague, exaggerated, or untestable claims o Over reliance on confirmation rather than contradiction o Lack of openness to testing by other experts o A o bsence of progress o Personalization of issues o Use of misleading language

Students understand and can describe sub-atomic structure

-Sub-Atomic Timeline

• Protons are positive (+)and located in the nucleus. • Neutrons re neutral (0) and are located in the nucleus. • Electrons are negative (-) and are located in the shells and have virtually

no mass. •

Students observe how models change over time

-Sub-Atomic Timeline -Gold foil experiment

• The model of the atom as we know it today is the result of many modifications and additions

Students can identify the importance, relevancy, and an example of Indirect Measurement

-Indirect Measurement Intro -Nuclear Marbles -Gold foil experiment

• Indirect measurement (def.): A technique that uses calculations to find a measurement when direct measurement is not possible.

o Ex) how we know what we know about atoms even though we cannot see them directly

Skills Based Goals Learning Goal Activity Observed

Students can Select a simple hypothesis, prediction, or conclusion that is supported by a data presentation or a model E.20.1

-EPAS practice (separate sheet)

Students can Identify key issues or assumptions in a model E.20.2 -EPAS practice (separate sheet) -Gold foil experiment

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During the following PowerPoint and demonstrations, fill in the blanks below with the words that are both BOLD and CAPITALIZED on the slides.

The Structure of Matter: A Historical Perspective

Prehistoric times

• Before 1000 B.C.E.

• People thought about matter for its ________________, not about what it was made of.

• They thought: “This could make a nice arrowhead,” not, “I wonder what makes this rock hard and shiny?”

Greek Theories

• The Greeks were ____________________________, not scientists.

• Because they had become “civilized,” they had more time to sit around, _________________ about, and

________________ what matter was.

• They did not do experiments.

Thales – 600 B.C.E.

• Thought that the simplest form of matter was _______________.

• He thought: Everything comes from water and depends on water; therefore water must be the

most basic of substances.

Anaximenes – 550 B.C.E.

• Thought that the simplest form of matter was _______________.

• He thought: Air can be condensed to form solids like the earth or can exist as we know it.

Heraclitus – 500 B.C.E.

• Thought that the simplest form of matter was _______________.

• He thought: All things are composed of fire and are again resolved into fire.

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Empedocles – 450 B.C.E.

• _______________________ the ideas of the Greeks before him but added _______________

as a component.

• Developed the _________________ _________________ __________________:

– All matter is made of 4 basic substances:

• ______________, ______________, _____________, and _____________.

Leucippus (the teacher) & Democritus (the student) – 450 B.C.E.

• Something cannot come from nothing.

• All matter is made of indivisible, indestructible ______________________ (____________)

• They thought: “The properties of a material are due to the arrangements of its atoms in

space.”

Democritus added:

• Atoms are in _____________________ ______________________.

• The __________________ of atoms determine their properties:

– Ex)

• Sour foods have sharp atoms.

• Sweet foods have large and round atoms.

Aristotle – 350 B.C.E.

• Disagreed with the atomic theory.

• Supported the 4 element theory and added the ____________ ______________________:

_______________, _______________, ______________, and ________________.

• Because he was known as the ________________ _____________________ in many things,

people had to believe him, and did so for 2000 yrs!!!

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Alchemy

•“_______________________ __________________________”

•Studied in many cultures from 5000 B.C.E. to present.

•It is a ____________________________________: _______________________________________________

_________________________________________________________________________________

•They develop models that do not fit the 3 criteria of a good model.

•Very secretive

The Philosopher's Stone

• The alchemists thought if they could find or create this substance, they could find or create their

three main goals:

1) __________ ______________________ _______ ___________________

• The _____________________ _______ ______________ that allows you to

live forever

• This would be worth ________________.

2) ____________________________ _______________________

• A liquid that would ____________________ ____________________

• This would be worth ________________.

3) ____________________________ _______ _________ ___________________

• _________________ cheap _____________ into silver and gold (Ag and Au).

• This would be worth ________________.

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Alchemists’ Contributions to Science

1) Discovered five ______________________: P, As, Sb, Bi, and Zn

The “ancients” already knew about: Au, Ag, Hg, Pb, Fe, Cu, Sn, and C

2) Produced a variety of ___________________________: test tubes, flasks, etc.

3) Refined and discovered ways of making things _____________: distillation, crystallization

4) Discovered ways of working with _________________: alloying

Post-Alchemy: The Beginning of Science

First Correct Recognition of an Element

• Even though ancients and alchemists knew of some elements, some

substances were incorrectly identified as elements.

• ____________________ ____________________ (1661)

– Developed the definition of an element.

– _____________________: __________________________________________________________

_______________________________________________________________________________.

– Ex) Water can only be broken down into O and H.

The Father of Modern Chemistry

• ____________________ ___________________ (1789)

– Had a _____________ of 23 substances, 21 of which are correct

with the elements we know today.

– Introduced _____________________________ ______________________________.

i.e. using numbers

Today, the story continues…

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Homework - IPS

Development of the Model of Matter

1) We studied three groups of individuals in the development of the model of matter: Greek Philosophers, Alchemists, and Scientists. Draw in the range of time that each group studied the model of matter on the timeline below:

I I I I I I I I I I I I I 600 500 400 300 200 100 0 100 1600 1700 1800 1900 2000(present)

B.C.E. B.C.E. B.C.E. B.C.E. B.C.E. B.C.E. A.D. A.D. A.D. A.D. A.D. A.D.

2) Who was considered the “great authority?” __________________________________ 3) Empedocles and Aristotle had similar ideas about matter. What aspect of their theories do they share?

______________________________________________________________________________________

______________________________________________________________________________________

4) What are the 4 elements represented in the Four Element Theory?

a. ______________________________________

b. ______________________________________

c. ______________________________________

d. ______________________________________

5) Of the Greeks, which 2 individuals are responsible for the theory that still fits our model of matter today?

______________________________________________________________________________________

6) Alchemy is a pseudoscience. Describe what this means in a complete sentence and in your own words:

______________________________________________________________________________________

______________________________________________________________________________________

7) List the 4 contributions alchemists have made to science

a. ________________________________________________________________________________

b. ________________________________________________________________________________

c. ________________________________________________________________________________

d. ________________________________________________________________________________

8) Define the term “element”? ________________________________________________________________

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Science vs. Pseudoscience

As a growing consumer of information and products, it will be an important skill for you to be able to distinguish between science and pseudoscience. Your teacher will provide you and your group with one of six ways you can identify a pseudoscience. In addition, you will be given a reading about a topic that is considered a pseudoscience. Your team’s job is to present to the class how your pseudoscience can be identified as such. After each presentation, we will summarize the main ideas in the chart below.

SCIENCE vs. PSEUDOSCIENCE Definition:

Definition:

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Review of the Atomic Model

As you learned in science class last year, all matter is made of _________________________. The Greek philosophers Leucippus and Democritus were the first to propose this model of matter. Our model of matter has come a long was from the Greek’s ideas about atoms. You may have also heard about the famous chemist John Dalton.

Dalton was the first person to weigh an atom. Of course, he could not pick up an atom and weigh it on a balance. How then did he arrive at the atomic weights listed in the periodic table? He thought that if he weighed larger amounts of the elements, and if these amounts contained the same number of particles, then he could weigh one atom relative to another. He chose hydrogen to be the standard (1amu) and weighed the other elements based on hydrogen’s weight. Dalton said that since Hydrogen is the lightest atom, it must also be the smallest in size. He published this first list of atomic weights in 1805.

Overall, even though

Dalton was not a good experimenter, he was a brilliant thinker. His faith in the existence of atoms contributed much toward promoting the Atomic Theory. In fact, atoms were so real to him that he could imagine their shape and size, he could write symbols showing how they combine and he could even weigh them. Dalton’s firm belief in atoms got others to believe his model as well. Today Dalton’s contributions can be summed up as follows:

Visualizing the Atom

Atoms are so small that scientists still have not been able to ___________ _____ ________. Using advanced computers, we can use STM (scanning tunneling microscopy) imaging. The computer then generates a visual ___________________ of the atom(s). Your teacher will now show you some of these amazing images. Draw or describe one of the images in the space below.

ATOMIC THEORY MODEL:

1. All matter is made of atoms that are ________________________. 2. All the atoms of ______________ ______________ are alike in weight and in all other properties.

3. The atoms of _____________ ______________ have different weights and properties.

4. Atoms are indestructible and preserve their _______________________ in all chemical reactions.

Modern Periodic Table

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Homework - IPS

Pseudosciences

Choose one of the following pseudosciences, do a little research, and fill in the graphic organizer bellow:

1. Lunar Effect 2. The Bermuda Traingle 3. Dowsing 4. Crystal healing

One way to identify a pseudoscience:

Another way to identify a pseudoscience:

Describe how your chosen pseudoscience can be identified by the method above:

Describe how your chosen pseudoscience can be identified by the method above:

Topic:

Description:

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TIMELINE: Development of the Sub-Atomic Theory

Around 460 B.C., the Greek philosopher Democritus asked: If you break a piece of matter in

half, and then do so again and again, how many breaks will you have to make until you can

break the matter no more? Democritus reasoned that one would eventually end up with the

smallest possible bits of matter. He named these basic matter particles atomos, or atoms. The

idea that matter is made up of fundamental particles called atoms is known as the Atomic

Theory of Matter. Recall though that the ideas of Democritus were opposed by Aristotle and were not commonly

considered until more than 2,000 years later.

It was not until the 1800’s that British chemist John Dalton began to revive the atomic theory of

matter by sharing the results of his experiments with others. Using various chemicals, Dalton

demonstrated that matter seems to consist of atoms. He published The Theory of the Atom in

1808, explaining that each element is made of small atoms of a certain type. He also proposed

that different elements have atoms of different masses. Dalton imagined atoms as tiny, solid

balls. Most importantly, he stressed that atoms were indivisible particles of an element. The true structure of atoms,

and thus the things that made them up, were still yet to be discovered.

In 1898, English physicist J.J. Thomson proposed a revised model of the atom. He had

discovered a subatomic (part of an atom) particle and called it an electron. Thomson reasoned

that since electrons carry a negative charge, the rest of the atom must be positively charged.

When he drew a representation of his atomic model, he drew a picture resembling raisins

(electrons) stuck in a muffin (positive area). Since he experimented with a variety of substances,

he concluded that atoms of different elements contain different numbers of electrons.

In 1904, the Japanese chemist Hantara Nagaoka proposed a model of the atom that had a large,

positively charged sphere in the center with electrons revolving around the sphere. His representation

was much like a picture of our solar system, with small planets revolving around a much larger sun.

Seven years later in 1911, New Zealand physicist Ernest Rutherford performed an experiment in

which he aimed atomic particles at a thin sheet of gold foil. He found that most particles passed right

through the foil, but some bounced back. These results suggested a model that most of an atom is

empty space. The data also suggested that almost all of the mass of an atom is contained in a tiny

141

nucleus. Rutherford affirmed the idea that the nucleus was positively charged, and offered that the positive charge

was a result of the subatomic particles called protons, which he had discovered. Rutherford disagreed with Nagaoka,

however, and thought that the electrons of the atom moved more randomly around the nucleus than the sphere

shaped path Nagaoka thought of.

In 1913, Danish physicist Niels Bohr insisted that electrons are not randomly located around the

nucleus, as Rutherford had thought, but were moving in specific spherical paths, or shells. In this

way, his representation was similar to the “solar system” model proposed by Nagaoka. Bohr was

actually able to calculate the distance between the nucleus and first energy shell and concluded

that all shells are at fixed distances from the nucleus. He said that atoms absorb or give off energy

when the electrons move from one shell to another.

At this point, it was a commonly accepted model that atoms were made of protons (positively

charged) and electrons (negatively charged) in equal numbers. In 1932, British physicist

James Chadwick discovered another subatomic particle, the neutron. He found the neutron

to have the same mass as a proton, but with no charge. The existence of the neutron

explained why atoms were heavier than the total mass of their protons and electrons AND

why atoms were neutral, overall, in charge.

The current model of the atom has resulted from further revisions of

those proposed in the past. Scientists working from the 1940s to the

present have developed the model that we accept today. Presently, the

scientific model says that atoms have a heavy, small, positively charged

nucleus made of protons and neutrons. The electrons are thought to

form a negatively charged “cloud” of sorts around the nucleus and it is

impossible to determine exactly where an electron is at any given time.

3n0

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Sub-atomic Structure Timeline

406 BC Democritus

1808 John Dalton 1898 J.J. Thompson 1904 Hantara Nagaoka 1911 Ernest Rutherford

1913 Niels Bohr 1932 James Chadwick

What the scientist discovered: What part of their model did we keep?

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Modern Model of Sub-Atomic Structure Notes 1. Basic Subatomic Particles and their Characteristics:

Subatomic Particle Name

Characteristic

Proton Neutron Electron

Symbol

Charge

Location in the atom

Discoverer

Date of discovery

Mass in grams

Mass in amu

(mass number)

2. Overall Structure of Atom

A. Nucleus

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B. Electron orbits, shells, or energy levels i. Elliptical path

ii. Electron cloud motion

iii. Relative distances

3. Size and Weight of the Atom – Need for new atomic size units

A. Mass

i. The atomic mass unit (amu)

• __________ g = _____ amu

• __________ amu = _____ g

ii. Range of masses

iii. Location of atomic mass

iv. Density of the nucleus

B. Length – the Angstrom unit (Å)

i. Diameter

a. Range of sizes

b. Diameter of nucleus 4. Visual Evidence for the Existence of Atom

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Indirect Measurement When scientists wanted to find out what an atom was, they were not able to look directly at what an atom was made of. They had to make inferences (educated guesses/extrapolations) from the results of many different experiments. It was like trying to describe the picture below, with only small portions visible.

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

______________________________________________________________________________________

______________________________________________________________________________________

______________________________________________________________________________________

______________________________________________________________________________________

______________________________________________________________________________________

______________________________________________________________________________________

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

______________________________________________________________________________________

______________________________________________________________________________________

VIEW “INDIRECT MEASUREMENT” POWERPOINT

Indirect measurement (def.) ____________________________________________________________________

_____________________________________________________________________________________________

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IPS – Indirect Measurement - Nuclear Marbles Lab

Purpose: To determine the diameter of a marble by indirect measurement. Procedure:

1. Work in groups of three (Recorder, Roller, and Returner) 2. Place nuclear marbles along wall 3. Without looking, roll the rolling marble at the nuclear marbles 4. Count and record how many trials and how many times a nuclear marble is hit by the rolling marble. 5. You must have 150 trials!

Data:

Trials Hits

Nuclear marbles________ Rolling marble ___1____ Calculations: Use this formula to calculate your marble diameter:

D = HL

2TN

Show your calculations here:

D = diameter

H = # of hits

L = 61 cm

T = # of trials

(150)

N = # of nuclear

marbles

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A Sophisticated Example of Indirect Measurement: Rutherford’s Gold Foil Experiment

View the following video to introduce Rutherford’s Gold Foil Experiment: http://nz.youtube.com/watch?v=5pZj0u_XMbc&feature=related

1) What is Rutherford measuring? _____________________________________________________________ 2) Why would this be considered and indirect measurement?

______________________________________________________________________________________

______________________________________________________________________________________

Now go to the following website: http://www2.ku.edu/~quarked/parents/lesson7.html Go to ‘follow up activities.’ Click on ‘Shape Sleuth.’ Try this activity.

3) How is this an indirect measurement?

______________________________________________________________________________________

______________________________________________________________________________________

4) How is this similar to Rutherford’s Gold Foil Experiment? _________________________________________

______________________________________________________________________________________

Look back at the Sub-atomic Theory/Structure Timeline. Notice that J.J. Thompson formulated a different model prior to Rutherford’s model.

5) Describe J.J. Thompson’s model here: __________________________

__________________________________________________________

__________________________________________________________

6) Do you think Thompson’s model explain the bouncing back of particles?

Why or why not? ____________________________________________

__________________________________________________________

__________________________________________________________

7) Which drawing to the right would best represent Thompson’s findings?

______________________________________________________

8) Which drawing to the right would best represent Rutherford’s findings? ________________________________________________________

Still having a hard time with this? Maybe this will help: http://www.mhhe.com/physsci/chemistry/essentialchemistry/flash/ruther14.swf

A)

B)

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IPS – “The Development of the Atomic Model of Matter” Review

Where appropriate, answer the following questions in complete sentences.

1) Describe the two different models of matter that were developed by the Greeks. Make sure to include the people involved in developing that model.

a. ________________________________________________________________________________

________________________________________________________________________________

b. ________________________________________________________________________________

________________________________________________________________________________

2) Explain what alchemy is and why it is not considered a science today.

___________________________________________________________________________________

___________________________________________________________________________________

3) Describe the model of the atom that Dalton developed.

___________________________________________________________________________________

___________________________________________________________________________________

a. How is it similar to the model that the Democratis and Leucippus thought of?

________________________________________________________________________________

________________________________________________________________________________

b. How is it different?

________________________________________________________________________________

________________________________________________________________________________

4) JJ Thomson changed our view of the atom. a. What did he discover that led him to change the model of the atom?

________________________________________________________________________________

________________________________________________________________________________

b. How did he describe an atom?

_________________________________________________

_________________________________________________

_________________________________________________

c. What part of Dalton’s model was found unacceptable based on Thomson’s ideas? ________________________________________________________________________________

________________________________________________________________________________

Draw:

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5) Define the following: Indirect measurement—

______________________________________________________________________________________

________________________________________________________________________________

6) Rutherford indirectly measured something about the atom. Explain what he measured and how he

measured it. ___________________________________________________________________________________

___________________________________________________________________________________

What makes indirect measurements so important in science? __________________________________

___________________________________________________________________________________

___________________________________________________________________________________

7) Draw and label a diagram of the atom we will be using in class.

8) What is meant when we say that “the atom is mostly empty space?” _____________________________ ___________________________________________________________________________________

___________________________________________________________________________________

9) Using the ideas of charges, the structure of the atom, and the knowledge that that atom is mostly empty

space, explain why you are not falling through the chair you are sitting on right now. ___________________________________________________________________________________

___________________________________________________________________________________

___________________________________________________________________________________

___________________________________________________________________________________