chemistryadventure test 1.25.2011

r r r r r r r r r

Our Essential Question for this unit:

Homework 1.1:

reader player

Introduction 2Table of Contents 3Lab 2.1: Mentos Eruption 4-8 Lecture 1.1: Data 9-14Worksheets 15-20Review 21-22

Names: Period:

Mentos Lab Report: Working Title

Most great discoveries begin with thorough research. Before filling out this form read the stunning

discoveries from the two previous Guilford Journals

1. Working Title: One sentence that states what you plan to discover. Odds are the title will change,

but its good for now. For example: Wax-coated Mentos reliably delay a Mentos Eruption, or Nozzle

size is Proportional to Mentos Eruption Height are some good working titles.

An excellent final title quantitatively states a significant new discovery.

3. A one paragraph summary of your experiment and results.

List your planned experimental procedure.

2. Your list of things to bring in next class:

Working Title:

3. Complete the tableUnit of measurement We usually use But SI units require

LengthMass

Temperaturedensity

6. Complete the table.Prefix Symbol Factor Scientific

notationexample

Gigamega

1,000centi

10-3

micro Microgram n

SI Units Unit Prefixesmeasurement unit symbol size Prefix Scientific

notationmass kilogram kg nano (n) billionth 10-9

volume liter L micro (m) millionth 10-6

distance meter m milli (m) thousandth 10-3

amount mole mol centi hundredth 10-2

brightness candela cd kilo k) thousand 103

current ampere A mega (M) million 106

time Second s giga (G) billion 109

m

weeks 4.43____

____x

days 31

___weeks ____

____ x

days 42

scentimeter 24.15inch 1

__________inches 6x

m

Summary10 points if you summarize your results using numbers to provide details. L1 and honors students- this is a good place to include your mathematical formula that states what you discovered. Be sure to explain the formula so that a stranger could understand it.

Introduction

This is where you describe the mentos eruption in general, and then explain what is known about your particular topic. All of your statements should be supported with references. The references need to be reliable, which means either the Coffey paper, or the Guilford Journal of Chemistry. No websites should be used as references. The citations look like this1 and the reference itself is at the end of the paper.

Experimental Procedure

This is where you provide a detailed, listed procedure that is repeatable by a stranger. Use numbers so the scale of your experiment is clear.Emphasize safety.

ResultsFor full credit, describe your results, and show them using a table and a graph.

Conclusion

This is perhaps the most important part, where you analyze your results and compare them to previous research. What can you safely conclude? How fuzzy is your data- is it tight and repeatable, or does it vary a lot with each trial? For L1 and honors students, this is where you show how your data fits a mathematical formula. Use that formula to predict what could happen if you were to extend your data out beyond your limitslike using a 4 liter bottle, for example.

For full credit, try to explain the reasons for your results. What is it about hot soda that makes the eruption go higher, for example. As we did in unit 1, try to answer on a molecular level.Also, suggest follow up experiments.

References

This is a list of peer reviewed books and journals that you are using to support your research. No websites may be used. The numbers correspond to the superscripts in the paper.In the end it should look something like this:

1. Kaitlyn Earles and Megan Graham, Guilford Journal of Chemistry, Volume 2, Pages 21-22 (2008).2. Tonya Coffey, American Journal of Physics, Volume 76, number 6, pages 551-337 (2008).3. Nick Hill and Kyle Gaboury, Guilford Journal of Chemistry, Volume 2, Page 38 (2008).4. Read page 553 of Coffey's paper (see reference 2) for a detailed analysis of the effect of pH on the height of a mentos eruption.5. Ryan Johnson and Will Graziano, Guilford Journal of Chemistry, Volume 2, Pages 9-11 (2008).6. Alex Jagielski and Eric Hedberg, Guilford Journal of Chemistry, Volume 2, Page 38 (2008).

For full credit include a minimum of 5 useful references formatted like the ones above.

unit 3

40

How do we find out what everything is made out of?

Unit 3

Look around you. What do you see? In front of you are all kinds of stuff- all sorts of matter. Some of this

matter you can see, and theres more that you cant.

Some substances, such as those in your body, are

undergoing transformations as we speak. And most of

it is all mixed together, which complicates things

further. Whats it all made out of? Its a big mess. What

we need to make sense of it is a way to sort things out.

Our primary goal for this unit is to classify the matter

that is all around us. First, well consider what we can

say about mixtures. As you might guess, not very

muchit varies from sample to sample. So, we will

explore some purification techniques. We will spend the

remainder of our time finding out what we can about

pure substances- these are the materials that the

universe as we know it is made from. And since nearly

all understanding of matter begins with pure substances,

purification is the first step in chemical research.

Heres the plan:

Lesson 1: Separation Lab

Lesson 2: Leaf Lab

Lesson 3 Matter Lecture

Lesson 4: Review

Lesson 5: Matter test.

A Liquid Chromatograph-Mass Spectrometer

(LCMS) can take a complex mixture, separate it,

and identify each substance. Shown above are the

major components of a tomato (a), mustard leaf

(b), and a strawberry (c), with some individual

substances (d-f) shown below based on their mass

spectrum.

Learn more by clicking on the image.

What is a tomato, mustard leaf, and a strawberry made out of?

Table of contents

sand

sand

sugar

salt

Method

pebbles

Iron filings

sugar

salt

pebbles

Iron filings Method

Methodsugar

salt

pebbles

Iron filings

sugar

salt

Iron filings

Iron filings salt

Method

Chemists typically spend more than half of their time purifying substances- separating them into their individual pure components. As a chemist it reminded me of cleaning up a mess at home. In this lab you will be given a mixture of 5 solid ingredients. Typically, these are sand, sugar, salt, iron filings, corn kernels, and pebbles. This year, they are:

1: __________2: __________3: __________4: __________5: __________6: __________

Your goal is to separate all ingredients of your mixture quantitatively, and analyze your results. You will be graded based on your choice of methods, your report, and percent error: how close your amounts are to the actual amounts provided.

Homework: Discuss this with your partner and come up with a plan. Write it as a diagram on the next page. You are welcome to use any equipment in the lab as long as you work safely and have it approved by me. Be ready to begin your experiment the following day. You will be allowed to dry any wet samples overnight.

Note that no student has yet come up with a quantitative method to separate salt from sugar.

Separation LabSome separation methods

to consider

filtration

Separatory funnel

decant

forceps evaporation boiling

Sample Separation Scheme

Invent your ownchromatography

Most common errors: -No separation or only partial separation of salt and sugar. -Samples still wet after overnight drying.

Separation lab (continued)Homework: Draw a neat diagram outlining your separation procedure, using the scheme shown on the following page. Note that you will have 60 minutes of class time only over two days to complete your separations.

Sand is an ingredient, but is not actually pure, as it contains hundreds of substances in addition to quartz (SiO2)

Separation Lab: Data

Mass of mixture ________ g

Mass of component 1 (__________) ________ g






Total mass of separated components _______ g

Percent Error ________ %

Your ScorePrecision: 1 point off for each percent error

_____ /10

Sample Purity (by inspection)

______ 10

Neatness and accuracyof report and analysis

_____ /10

Total _____ /30

Analysis: Write a paragraph summarizing your experiment, and reflect on the results. Be sure to include recommended improvements if you were to repeat the process. Use additional paper if necessary.

Once you have the stamp of approval, begin your separations. Time your work so that any sample drying takes place overnight. When you are done place each sample in a labeled plastic bag, and ieach ndividual bag in a final plastic bag- your instructor will model it for you. You will be graded based on the purity and amount of each sample. Fill in the data table and complete the Analysis section below.

The matter all around us is rarely in a pure form; most of what is around us are mixtures. Perhaps the most complex mixtures are those in living things. To understand what is in a mixture we must separate the individual substances contained in a mixture.

In our very first experiment you each planted a seed and by now you should have several leaves. The goal of this experiment is to isolate some pure substances from that leaf. If you have need to, bring in some fall leaves from home.

Lab 3.2

Every leaf contains thousands of individual chemicals. Well focus on three visible groups with characteristic fall colors: the carotenes, xanthophylls, and chlorophylls. Their chemical structures and typical colors are shown on the right

Background:

Chromatography (color writing) is a powerful tool for purifying mixtures. We will use paper chromatography to isolate the visible substances in a leaf. To do this we will make a thin paste of leaf goo using a powerful solvent (methanol), then paint it on chromatography paper, which is our stationary phase. We then place it in a jar that has some organic solvent on the bottom (our mobile phase, and allow the solvent to move up the paper, separating the mixture based on the adherence to the paper, and the solubility in the solvent.

Your task is to find a solvent system that will separate the mixture.Watery solvents such as methanol or acetone tend to dissolve everything and move the mixture rapidly. Greasy solvents such as hexane dont tend to move the mixture much at all.

Try a few combinations until you get nice separation, like the chromatogram shown below. Not the identity of each band, and how the distance traveled by the substance is measured using Rf value, where all the way up to the solvent front has a value of 1, and the baseline has a value of zero.

Carotenes: Gold to Orange

Xanthophylls: Light Yellow

Carotenes Rf = 1.0

Chlorophyll B: Olive Green1. Which is more greasy (hydrophobic): the carotenes or the xanthophylls?2. Which is more greasy: chlorophyll A or B? Why?

Xanthophylls Rf 0.37

mystery substance Rf 0.32

Chlorophyll A Rf 0.21

Chlorophyll B Rf 0.16

Chlorophyll A: Forest Green

Tape your chromatogram here. Identify each band and measure its Rf

value.

Using the techniques described in this lab report and demonstrated by your instructor, find a solvent system that provides optimum separation of visible leaf constituents.

Tape your best chromatogram to this lab report and measure the Rf value of each visible substance.

Note that your values do not have to match those on the previous page.

Solvent system used:_____% ____

_____% ____

Tape your best chromatogram to this lab report and measure the Rf value of each visible substance.

Note that your values do not have to match those on the previous page.

Score:

Prelab questions: _____/3Separation: _____/3Identification: ____/3Rf measurements: _____/3Total: ___/12

1. What is it? 2. Mixtures: types 3. Mixtures: purification3. Pure matter and its properties 4. States of matter 5. Liquid crystals

Element, molecule, or mixture?

element element moleculemixture mixture

gold ocean milk copper glass

Think of an example of each.Element: Molecule: Mixture:

MatterUnit 3

How do we find out what everything is made out of?

Our essential question:

A good place to start:

Classify it.

Matter

Nothing is pure in this world.What can we say about mixtures?

Looks pure but isnt

doesnt look pure

homogeneous heterogeneous

One thing visible

Multiple things visible

Either way its still a mixtureuntil it is separated we dont know much about it.


Solutions: Gas-gas:

Gas-liquid:

liquid-liquid:solid-solid:

solid-liquid:

air

soda

Gasoline; vinegar

Salt water

brass;steel

a solution a mixture

want pure:


Purification: How to separate mixtures.

oil: sand sugar

Technique:

decant

filter

crystallize

distill

chromatograph

oils All.

You have

Physical vs. Chemical Properties of Matter

Stays the same New substance(s) formed

Physical Properties include:

Chemical Properties include


flammability rust

Melting point density magnetism malleability

ductility

color Boiling point crystallinity Refractiveindex

luster

Extensive and Intensive Properties

Melting point

density Refractiveindex

mass

toxicity

in

inin

ex

ex


crystallineamorphous

amount-dependent

extent

Doesnt matter how much

melt

boilcondense

deposit

cold

hot


liquid

solid

gas

Phase Changes

freeze

sublime


5 states of matter

hot

coldsolid

Liquidcrystal

liquid

gas

plasma

no

Yes-But

ordered

Yes

FillsContainer?

Yes

no

no

no

no

yes

no

no

no

no

yes

??

State?AssumesShape ofContainer? Compressible?

Liquid crystals and plasmas


Coming next: the atomL2: End matter

Ordered liquids charged gases

Nematic liquid crystal:

Linear alignment

Smectic liquid crystal:

Planar alignment

Modern Separation Methods (L1, honors only)

Still in Use

Layer separation filtrationcrystallization

Vacuum distillation Spinning band distillation

distillation

Paper chromatography

High performance liquid chromatography (HPLC)

Gas chromatographyThin layer chromatography

Still in use

Melting point Boiling point

Nuclear magnetic resonance spectroscopy (NMR)

Mass spectrometry

All-in-one

LCMS

Flame ionization

Classical Identification Methods (L1, honors only)

Modern Identification Methods (L1, honors only

Infrared spectoscopy

Classify each of the materials below as an element, molecule, or mixture. The examples below should help get you started. Its OK if you miss a fewthis is to get us thinking about what things are made out of. A key will be passed out after you complete this.


A. SilverAnswer: Silver is an element (Ag).B. AirAnswer: air is a mixture of nitrogen (an element), oxygen (an element), and, among other things, carbon dioxide (a molecule).C. IceAnswer: ice the solid form of water, which is a molecule (H2O).

Classify the 19 materials on the next page, then check the answer key to see how you did.

What is everything made out of?

What is a diamond ring made out of?

Classifying Matter ws 3.1What is everything made out of?

Our essential question for this course:

*You should be aware that many texts differentiate between molecules and compounds. In this class we wont go there. If youd like to see the confusion that it can lead to, click here or here.

To say that the universe is made out of matter is true, but doesnt provide much detail. It would help to classify mater.. Lets start with elements.

The universe as we know it has about 100 elements. Occasionally we see them in their isolated form- for example an engagement ring may be pure gold (Au), with a diamond on it, which is pure carbon (C ).

More often we see the elements bonded together to form molecules, such as water (H2O) or table salt (NaCl). Sometimes called compounds,* molecules are made out of multiple elements which are bonded together and they have constant physical properties. For example, water freezes at 0 oC, and table salt melts at about 2000 oC.

If we look closely at the things around us, we find that most of them are mixtures of molecules. Drinking water, for example, is mostly made out molecules of water, but also has some molecules of salts (like NaCl) and may have be fluoridated as well.


Material Element?

Molecule? Mixture?

A. Silver B. Air C. ice 1. Mud2. sugar3. steam4. Baking soda5. Alumninum foil6.brass7. blood8. Bubble gum9. gatorade10. chalk11. glass12. Soy sauce13. grasshopper14. gasoline15. urine16. snow17. milk18. tobacco

19. Pencil lead (graphite)

20. Look around you. Try to find examples of elements, molecules, and mixtures in front of you right now.

1. An element in front of me:______ 2. A molecule in front of m:________3. A mixture in front of me:________

21 (L1, honors only)Use the following 6 definitions to make a classification chart similar to the one at the end of unit 1. A sample to get you started is at the bottom right of page 18.

Matter: Anything with mass and space.Element: A substance with a fixed number of protonsMolecule: Atoms bonded togetherCompound: Different atoms bonded togetherMixture: More than one substanceSubstance: A pure form of matter

each of the 7 words below on your chart as examples. Consider if some should go in more than one place.. Also ask yourself if pure elements are bonded together.

Oxygen (O2) Water Iron Carbon Diamond Graphite Sodium chloride

Matter classification chart (L1, honors only)

Humans love to classify everything.

ws3.3

A walk on the beachIntroduction to Matter Summary Worksheet

While walking down the beach one day, I spied a small object. I noticed it has both mass and took up space, so I was sure it was ___________. I picked it up and took a look at it under a magnifying glass. I could not see any impurities in this glassy object, therefore I was pretty sure it was _____________________. I assumed it was pure, so I classified it as a ____________________.

I took it home and heated it over a fire, but it did not melt, so I cant really say anything about that __________________(physical, chemical) property. I hammered it and it did not flatten; it is not _____________. I tried to stretch it and could not; it is not _______________. This material is a colorless solid. By the way, The other states of matter are ___________, _____________, and _____________. A few believe that _____________ represent a fifth state of matter, and this phase could either be in a ____________ or _____________ state. My little rock is just a simple solid. Since it is shiny I could say it is ___________. If I had the right equipment I could heat it up to a liquid (_________ it), or perhaps even heat it further from a liquid to a gas (_______________). Its possible that when I heat it up it might go directly to a gas (_______________), but I doubt it. I do know that iodine vapors can cool directly to form a solid (_______________), but that has nothing to do with my story.

I happened to have some hydrofluoric acid kicking around, and when I dropped in my substance to that nasty acid, it dissolved. That _____________(physical, chemical) change was weird. I sent it out to an analysis lab and they told me that my 600 milligram sample consisted of 280 milligrams of Si (_______________), and the rest was O (_______________). The percent composition of my sample is therefore _______% Si, and ________% O. And I thought my substance was a pure element, but really it is a just a _________. I submitted several similar samples I found at the beach and they all gave exactly the same analysis; this data is very ___________. I assume the people at the lab know what they are doing so it is probably __________ as well. L1 and honors students know that if I could prepare a solution of my substance I could puriy it and have the minor impurities identified using a single machine known as a ___________.

But Im pretty sure I know what it is already. My substance is______________.

CrystallineAmorphousMatterSubstanceCompoundSolidGasHeterogeneous

HomogeneousLiquid crystalLiquidSublimationDepositionBoilingMeltingCondensation

ChemicalPhysicalSiliconOxygenOzonePreciseaccurate

ws3.4

I need it PureModern Purification and identification methods worksheet

After listening to the matter slideshow, especially the last two slides on modern methods of sample purification and identification, answer the questions below using some but not all of the words below

Place an I in front of each term above that refers to compound Identification, and a p in front of methods used for Purification

1. Which method is best for separating oil from water? __________________________2. Which method is best for separating two liquids whose boiling points only differ by one degree Celsius? ________________3. Which method is appropriate to separate 5 mg of a solid organic substance? _______________4, Id like the elemental composition of a pure metal. A good method would be______________5. Id like to separate a separate a sample of Martian Air into its individual componentsa good choice would be:______________________________6. This method of sample identification is used for organic compounds, and although it provides a nice fingerprint of the substance, has been largely replaced by more informative methods such as___________7. This method of sample identification creates predictable peaks based on the composition of the elements next to the point in question._________________________8. This method of sample identification produces a molecular ion which is a good measure of the molecular weight of the substance._______________________________________9. This is an old method of purification still in use, gives incredible sample purity, and was used in the rock candy experiment __________________________________10. This will do for separating oil and water __________________________________11. For the separation of complex mixtures which can be dissolved in a solvent, this method is hard to beat._________________________________________12. Used in the leaf lab, this method will separate a crude sample into many individual substances but is rarely used professionally. ____________________________13. This is the ultimate solution: it will separate and identify just about any solution, no matter how complex.___________________________________

We have seen how substances may be classified based on how their atoms are arranged (for example functional groups such as aldehydes, ketones, etc.). They may also be grouped into their 5 physical states, their physical, or their chemical properties.

A chemist spends the majority of his or her time purifying mixtures, and we spent some time doing that. We used basic techniques such as decanting, filtration, distillation, and chromatography to isolate some pure substances from a mixture. L1 and honors students explored the modern equipment used for separations including high performance liquid chromatographs and spinning band distillation devices. All students learned basic methods to identify pure substances such as odor, melting point, and conversion to known compounds. L1 and honors students also learned about modern spectroscopic methods to identify substances such as nuclear magnetic resonance (NMR) spectrometers. Finally, they had a glimpse at the future with some state of the art devices that can purify a mixture and identify each substance in it such as a LC-MS (liquid chromatograph-mass spectrometer).

To ace this test be sure to understand the packet, including all lab experiments, slides, and worksheets. Go online and watch the screencasts of the slides if necessary. Be ready to separate a mixture if given one. Take a brief look at the first two units, since they are fair game on a test. Review your notes from your lab notebook, including all demonstrations and chalk talks. Finally consider the significance of the long term experiments we have been monitoring- the rock candy lab, and the seed lab. In our next unit we will zoom in enormously from our macroscopic view of matter and will ask ourselves what the smallest building blocks of matter are- this is the atom unit coming up next.

Be able to provide detailed answers to the questions below.Have a thorough understanding of the concepts below. Be able and ready to separate a mixture if given one.

Howtoaceitunit3

How to ace the Matter test

In this our third unit we learned how to purify and classify matter. Matter in its natural state is a mixture of substances, and to study them we purify and identify them, and determine their properties. The mixtures may look pure (homogeneous) or many things may be visible (heterogeneous). The pure substances occasionally are composed of only one element, but more often are molecules that consist of multiple elements bonded together. There are a nearly infinite number of individual substances on earth, and chemists have learned how to mak evirtually any new substances (though not always very quickly) of their own design.

1. What is matter?Matter is_____________________

2. What is a substance?A substance is a __________ _________ or ____________

3. What is a physical property?

4. What is a chemical property?

5. How could I separate sand from aluminum powder?

6. What are the 5 states of matter?

7. Where can I observe plasma?

8. What are liquid crystals?

9. What are the two types of liquid crystals and how do they differ?

10. Describe the six conversions of matter states (boiling, melting)

11. What is the law of conservation of mass?

12. Define malleable and ductile and give examples of each.

13. Heterogeneous mixture = ___________________; homogeneous mixture =___________________Homogeneous mixtures can be solid/liquid (______________), liquid/liquid (______________), gas/liquid (______________), gas/gas (______________), or even solid/solid (______________).

14. How to separate mixturesa. Sugar from sand

b. Iron from sand

c. Water from the ocean

d. Blue ink from black ink

15. What is an element?

16. What is a compound?

17. Why is chromatography such a powerful method for the separation of chemical mixtures?

18. Draw a chromatogram of a sample that has a Rfof 0.75

19. What does HONC mean?

20. Draw propanol, C3H8O using both a structural and skeletal formula.

21. Draw two isomers of butane, C4H10,

22. To put this unit in perspective, modify the conceptual diagram at the end of unit 1 to include the main concepts of the matter unit.

22. What is an atom? This is our next unit.

Poison Ivy (Toxicodendron radicans, shown at left) produces the urushiol class of allergens, including the one shown

urushiol

Toxicodendrons radicans (poison ivy)

Unit 4: the atom

The AtomUnit 4

How do we know that the world is made out of atoms?

A historical approach.

Page 69

Unit 4: the atom

DemocritusAtomos

Evidence: nothing

AristotleEarth, Air,

Fire, Water:Phases!

GhazaliAlchemist

We can splitthe atom

LavoisierBalance:

IndestructibleConservation

of mass

Mikhailovskij field

emission electron

microscopy (FEEM)Atomic image

including orbitals

Dalton: bondsAtoms

combine in small whole

numbers

ThomsonElectrons

Plum pudding

Rutherford1790

jimmy neutron

History of the atom worksheet ws 4.1

Complete this worksheet after listening to the presentation on the history of the atom from 400 BC to

1907 AD. Refer to the notes on your slides if you need to for each question.

1. What is the essential question for this course?

2. What is the essential question for this unit?

3. What would you need to see, know, or observe to become convinced that atoms exist?

4. By now you have seen a presentation on some ideas and experiments concerning the atom from about

2400 BC to 1907. Fill in the table below to summarize the work and significance of some of the key

players.

name Democritus Aristotle Ghazali Lavoisier Dalton Thomson Rutherford

Symbol

Contribution

5. How is Daltons model of the atom different from that of Democritus?

6. Draw a picture of the Cathode Ray tube used by Thomson, identifying each component. Show 2

experiments that indicate the green light in the tube is in fact not light.

7. Light is a form of electromagnetic energy and has no mass. Compare that to the green light in the

cathode ray tube.

8. How might the gold foil experiment suggest the shape of an atom?

9. How big is an electron compared to a hydrogen atom?

10. Draw a figure and explain Rutherfords Gold foil experiment:

11. Lavoisiers experiments indicated that mass is never lost when chemical reactions

occur.

Daltons experiments suggested that elements come in different sizes, and they combine in

simple ratios. Thomson showed there is something smaller than hydrogen, and Rutherford

showed that there is a lot of empty space in matter. Based on those experiments and a

hunch that the atom may resemble our solar system, the early 20th century model of the

atom is the Jimmy Neutron symbol.

To understand the atom is to understand all matter on its most basic level. What did they

still NOT know about the atom at this point? List as many things as you can.

Atomic Bookkeeping Worksheet ws 4.2 Atomic Particles, Atomic Number, Mass Number, Ions, and Isotopes

Here are some quick facts to help you keep track of the names and numbers associated with the atom:

1. Pick an element, any element. My element has the symbol _______, which stands for

____________. It has ______ protons, and when uncharged also has _________ electrons. The

average atomic mass of this element is ________ atomic mass units. If it has one extra electron, this

would give it a _____ charge. If one atom had two more neutrons than protons, the mass number would

be ________ atomic mass units.

2. Fill in the blanks below:

____________average atomic mass

____________chemical symbol

____________chemical name

____________atomic number

3. Complete the following table:

Element Number of

protons

Number of

electrons

Average

atomic mass

O (oxygen) 8 15.999

Zn (zinc)3+

Sn (tin)-

Fe (iron)3+

C (carbon)

H (hydrogen)+

Sg (seaborgium)

4 What is an isotope?

5. What is the difference between mass number and atomic number?

Hydrogen

1

H

1.008

Protons are in the nucleus, each has a +1 charge, and identifies the element.

Neutrons are in the nucleus, each has no charge, and determines the isotope.

Electrons are outside the nucleus, each has a -1 charge, and determines the reactivity.

Atomic Number is the number of protons.

Mass number is the number of protons + neutrons

Average atomic mass is the averaged mass for a mixture of isotopes

An ion has either more or less electrons than protons, so it is charged.

Isotopes vary only in the number of neutrons for an element.

Atomic mass/average atomic mass worksheet 1. Complete the following table:

Element Number of

protons

Number of

electrons

Number of

neutrons

Mass number

O (oxygen) 8 8 9 17

Zn (zinc) 37

Sn (tin) 118

Fe (iron) 30

C (carbon) 14

H-(hydride)

Note the

negative sign!

0

Sg

(seaborgium)

266

2. Mass number and atomic number are easy to confuse. To determine atomic number one only needs to know the number of _____________, whereas the mass number also includes

the number of_____________.

3. Chlorine has two naturally occurring isotopes, Cl-35 and Cl-37. The lighter isotope is _____ which contains _____ protons and _____ neutrons. The heavier isotope is _______

with _____ protons and _____ neutrons.

4. Here is a problem that is solved for you. As you read the problem, imagine how you could solve it without a calculator, then see how it is done, and apply the solution to #5.

An imaginary element X has two isotopes, one with a mass of 20 atomic mass units (amu), and the other with a mass of 22 amu. They both occur with equal (50%) abundance. What is

the average atomic mass of X?

Solution:

(0.5)(20) + (0.5)(22) = 21 a.m.u.

5. What would the atomic mass of element X above be if the abundances of X-20 was 25%, and the abundance of X-22 was 75%?

Solution (fill in the missing numbers: ( )( ) + ( )( ) = _____ a.m.u.

6. Silver has 2 isotopes. One has a mass of 106.905 amu (52%) and the other has a mass of 108.905 amu (48%). What is the average atomic mass of this isotopic mixture of silver?

Isotopes, ions, atomic mass, and average atomic mass worksheet ws4.3

The number of protons, electrons, and neutrons is usually symbolized in an element box in the

following manner:

For example:

Once the number of each atomic particle is known, it is an easy matter to identify isotopes (atoms

that vary only in the number of neutrons) or ions (atoms that do not have the same number of

protons and electrons).

1. Fill in the blanks

2. Which pairs of elements are isotopes?

3. Which elements are ions?

4. Fill in the boxes below.

F-9

19

Ca20

41 2+

U92

235

9 protons

10 neutrons

10 electrons

20 protons

21 neutrons

18 electrons

92 protons

143 neutrons

92 electrons

S 16

32

Cl 17

35

U 92

238

___protons ___ neutrons ___electrons



4+

S 16

34

Cl 17

35

U 92

238




6+ -

7 protons 9 neutrons 8 electrons


8 protons 8 neutrons 8electrons

1 protons 0 neutrons 1 electron



Na + 11 24

Mass number (p + + n 0 )

atomic number (p + )

Charge (p + + e - )

5. Are the following pairs of compounds isotopes, ions, or different elements? Also, provide the full atomic

symbol for each substance

Example:

a. Substance 1: 10 protons, 10 neutrons, 10 electrons:

b. substance 1: 10 protons, 11 neutrons, 10 electrons

Relationship: isotopes

c. Substance 1: 10 protons, 10 neutrons, 10 electrons

d. substance 1: 9 protons, 10 neutrons, 10 electrons

Relationship:________________

e. Substance 1: 10 protons, 10 neutrons, 11 electrons

f. substance 1: 10 protons, 10 neutrons, 10 electrons

Relationship:________________

6. Determine the average atomic mass for the following imaginary elements, using the first question as an

example.

a.

Isotope 1: 14 protons, 14 neutrons.

Abundance: 62%


Abundance : 38%

Average atomic mass =

b.

isotope 1: 94 protons,104 neutrons.

Abundance : 52%


Abundance: 48%

Average atomic mass =

c.


Abundance : 40%


Abundance : 39%

Isotope 3 : 24 protons, 28 neutrons

abundance = 21%

Ne10

21

3. Level One Only: Boron has two naturally occurring isotopes. Boron -10 (abundance = 19.8%; mass =

10.013 amu) and another isotope (abundance 80.2%). The average atomic mass of boron is 10.811 amu.

What is the mass of the other isotope?

Solved Example.


Abundance : 91%


Abundance : 9%

Average atomic mass = sum of

(abundances)(mass number)

= (0.91)(8 amu) + (0.09)(9 amu)

= 8.09 amu

Howtoaceitunit4

How to ace the Atom unit

In this our fourth unit, we explored the atom. Our goal was to answer the question: How do we know that atoms exist? We began with a chronological study, starting with the ideas of Democritus, and

ending with the discovery of the nucleus by Rutherford. We also considered what it would take to

convince us that atoms in fact do exist, and we found evidence that atoms have been individually

observed and moved.

We then focused on the three primary subatomic particles. We considered their location, mass and charge, and this led to an understanding of atomic number, mass number, and average atomic mass. Finally, we applied this to isotopes, and finished with the band of stability- the ratio of protons to neutrons for a stable atomic nucleus.

In our next unit we will focus on the subatomic particle that determines the chemical behavior of each

element: the electron.

To ace this unit you should review the powerpoint slides, the atom worksheets, and this study guide.

You should also review the results of our Seeing the Atom project. Here are some quick questions on

each topic we covered.

1. The history of the discovery of the atom:

a. Aristotle and his four elements

b. Democritus: symbol and what he got right

c. Paracelsus: Symbol and contribution

d. Lavoisier: Symbol, contribution, and his untimely end

e. Dalton: symbol and his major contribution

f. Thomson: symbol, what he discovered, device he used, evidence

.

g. Rutherford: symbol, and his key experiment

2. The 3 subatomic particles, their mass in atomic mass units (amu), and charges

3. Atomic number

Example: What are the atomic numbers for each element in baking soda, NaHCO3? Why can Magnesium never have 13 protons?

4. Mass number

Example: What is the mass number of an oxygen atom that has 8 neutrons and 9 protons?

5. Average atomic mass formula

Example: Element X has two isotopes. One has an abundance of 63% and an atomic mass of 10 a.m.u. The other has an abundance of 37% and an atomic mass of 15 a.m.u. What is the average atomic mass of element X?

6. Isotopes- definition (watch out for cases that are different elements, not different isotopes)

Example: How many protons and neutrons are present in an atom of Cs-111?

7. Ions- know how to calculate charge on an atom

Example: How many protons, neutrons, and electrons are present in an atom of C-13? Example: Draw element boxes that show an example of a fluoride monoanion (-1), and a calcium dication (+2).

8. Nuclear stability

Example: Circle the stable isotopes: U-238 Po-208 C-14

9. Chemical symbols for elements 1-20

What are the symbols for hydrogen, helium, lithium, beryllium, boron, carbon, nitrogen, oxygen, fluorine, neon, sodium, magnesium, aluminum, silicon, phosphorus, sulfur, chlorine, argon, potassium, and calcium,?

10. How do you know that atoms exist? Provide quantitative evidence in addition to imaging.

Be sure to review the Seeing the Atom Presentations from each of you. Good luck on the test.

Howtoaceitunit4

How to ace the Atom unit

KEY

In this our fourth unit, we explored the atom. Our goal was to answer the question: How do we know that atoms exist? We began with a chronological study, starting with the ideas of Democritus, and

ending with the discovery of the nucleus by Rutherford. We also considered what it would take to

convince us that atoms in fact do exist, and we found evidence that atoms have been individually

observed and moved.

We then focused on the three primary subatomic particles. We considered their location, mass and charge, and this led to an understanding of atomic number, mass number, and average atomic mass. Finally, we applied this to isotopes, and finished with the band of stability- the ratio of protons to neutrons for a stable atomic nucleus.

In our next unit we will focus on the subatomic particle that determines the chemical behavior of each

element: the electron.

To ace this unit you should review the powerpoint slides, the atom worksheets, and this study guide.

You should also review the results of our Seeing the Atom project. Here are some quick questions on

each topic we covered.

1. The history of the discovery of the atom:

a. Aristotle and his four elements

cross, AFEW

b. Democritus: symbol and what he got right

Ball; the world is made out of atoms

c. Ghazali: Symbol and contribution

split ball; suggested we could split the atom

d. Lavoisier: Symbol, contribution, and his untimely end

balance; atoms may be indestructible; guillotined

e. Dalton: symbol and his major contribution

barrel omonkeys; bonds

f. Thomson: symbol, what he discovered, device he used, evidence

.plum pudding; electrons; cathode ray tube; magnet, propeller, and mass to charge ratio

g. Rutherford: symbol, and his key experiment

james Isaac neutron; gold foil

2. The 3 subatomic particles, their charges

P+, N0, E-

3. Atomic number

Example: What are the atomic numbers for each element in baking soda, NaHCO3? Na 11, H1, C6, O8 Why can Magnesium never have 13 protons? Yo thats aluminum bro

4. Mass number

Example: What is the mass number of an oxygen atom that has 8 neutrons and 9 protons?

17

5. Average atomic mass formula

Example: Element X has two isotopes. One has an abundance of 63% and an atomic mass of 10 a.m.u. The other has an abundance of 37% and an atomic mass of 15 a.m.u. What is the average atomic mass of element X? We estimatemost of it is 10, some of it is 15about 12

6. Isotopes- definition (watch out for cases that are different elements, not different isotopes)

Example: How many protons and neutrons are present in an atom of Cs-111? 55P,, 56N

7. Ions- know how to calculate charge on an atom

Example: How many protons, neutrons, and electrons are present in an atom of C-13? 6P, 7N, 6e Example: Draw element boxes that show an example of a fluoride monoanion (-1), and a calcium dication (+2). Heres the list: F- has 9P, 10e, average atomic mass of 18.9 amu

Ca +2 has 20 P, 18 e, and an average atomic mass of 40.0 amu

8. Nuclear stability

Example: Circle the stable isotopes: U-238 Po-208 C-14

9. Chemical symbols for elements 1-20

What are the symbols for Refer to periodic table hydrogen, helium, lithium, beryllium, boron, carbon, nitrogen, oxygen, fluorine, neon, sodium, magnesium, aluminum, silicon, phosphorus, sulfur, chlorine, argon, potassium, and calcium,?

10. How do you know that atoms exist? Provide quantitative evidence in addition to imaging.

Please be prepared to write a persuasive essay.

Be sure to review the Seeing the Atom Presentations from each of you. Good luck on the test.

Unit 4: the atom

How do we know that the world is made out of atoms?

List 2 types of evidence that would convince you personally that atoms do in fact exist:

1.

2.

Democritus400 BC

ballAristotle350 BCcross

Ghazali1100

split ball

Lavoisier1790

balance

Mikhailovskij 2009picture

Dalton1820

earrings

Thomson1905plum

pudding

Rutherford1790

jimmy neutron

Within the framework of this approximation, the

compres-sion factor is given by

f = (r0/L)1/2, (1)

where L is the total distance of the apex of the

hemisphere from the paraboloid surface (L=l+p0)

and is a numerical

constant which is almost independent of

congurations of chains and supporting tips and has an approximate value of 1.145.17 The apex

eld-enhancement factor for the chain on a paraboloid model is given by -=1.05(2+L/p0)0.99.

The eld F at the end of the chain anchored at the apex of a parabo-loidal tip can be shown to

be F=2-V/r0 ln(2R/r0). Using these expressions,

the calculation yielded the following ex-pression

for the minimal diameter of resolved emission

spots in FEEM images of free-standing linear

nanoobjects:

1/4eme

0 = (21 p0)1/2[-LF ln(2R/r0)]. (2)

Imaging the atomic orbitals of carbon atomic chains with eld-emission electron microscopy

I. M. Mikhailovskij,* E. V. Sadanov, T. I. Mazilova, V. A. Ksenofontov, and O. A. Velicodnaja

Department of Low Temperatures and Condensed State, National

Scientic Center, Kharkov Institute for Physics and Technology,

Academicheskaja, 1, Kharkov 61108, Ukraine (Received 17 July

2009; revised manuscript received 2 September 2009; published 7

October 2009)

A recently developed high-eld technique

of atomic chains preparation has made it

possible to attain the ultrahigh resolution of

eld-emission electron microscopy (FEEM),

which can be used to direct imaging the intra-

atomic electronic structure. By applying

cryogenic FEEM, we are able to resolve the

spatial conguration of atomic orbitals, which

correspond to quantized states of the end

atom in free-standing carbon atomic chains.

Knowledge of the intra-atomic structure will

make it possible to visualize generic aspects

of quantum mechanics and also lead to

approaches for a wide range of

nanotechnological applications.

DOI: 10.1103/PhysRevB.80.165404 PACS

number(s): 61.05.-a, 68.37.Vj, 81.07.Vb

DemocritusAtomos

Evidence: nothing

AristotleEarth, Air,

Fire, Water:Phases!

GhazaliAlchemist

We can splitthe atom

LavoisierBalance:

IndestructibleConservation

of mass

Mikhailovskij field

emission electron

microscopy (FEEM)Atomic image

including orbitals

Dalton: bondsAtoms

combine in small whole

numbers

ThomsonElectrons

Plum pudding

Rutherford1790

jimmy neutron

Unit 4: the atom

22 n

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Names___________________________________________Period______________ lab5.1

Flame Tests Lab

20 points

Safety Notice: This lab is exciting, but please be cautious. Wear goggles. Assume all salts are toxic, as

are all gases produced.

Introduction: We have all seen the beautiful colors that can form when substances are placed in a flame.

Pockets of gas in wood can form green and blue colors when they ignite. What is happening when this

occurs? This answer was the key to unlocking the secrets of the electron, now known as quantum theory.

In this experiment we will observe some of these colors, and will make some initial attempts to explain it.

Finally, the color of the emitted light will be used to identify the unknown salts.

Chart: Wavelength (in nanometers) of visible light

Table 1: Color and wavelength in nanometers of emission spectrum of salts and unknown.

Salt Flame color Estimated wavelength

(nm)

1.

2.

3.

4.

Unknown #_____

Unknown #_____

Analysis

1. Each of the known compounds tested contains chlorine, yet each compound produced a flame of a

different color. What does this suggest?

2. We will learn this week that the movement of electrons in atoms produces the colors we observed.

What specifically may be going on with the electrons to produce color? (take your best guess)

3 (l1, honors only) .Using the periodic table below, draw the color of light for each cation observed,

and look for a pattern.

4.Based on the colored periodic table above, and your best guess as to what may be going on with the electrons, fFind

a pattern and describe it in one sentence: 5. Based on this pattern predict the color observed when each salt is exposed to a flame:

Calcium chloride______________ Cobalt chloride_______________ Zinc chloride______________

Team Names_________________ and ____________________ Period _____ Lab 5.2

Spectroscopy Lab

Introduction: In our previous lab we observed the vivid colors emitted by placing chloride salts in a

flame. This was followed by a demonstration where we observed how a spectroscope (a prism, really) can

divide up light into separate wavelengths. We now know our eyes can only see a tiny section of the

electromagnetic spectrum shown below:

The purpose of this lab is to combine these two observations by repeating the flame test experiment,

this time using a spectroscope. This experiment is similar to that performed by Niels Bohr and others,

and begs the question: what does it all mean? How do the spectral lines relate to the structure of the

atom?

Safety: As before, this lab uses flames and toxic salts. Please wear goggles.

Procedure:

1. Put on goggles.

2. Each group will perform a 5 minute experiment at each of 6 stations, and then proceed to the

next. As precisely as you can, draw the component wavelengths observed at each station. Follow

the instructions for each station, clean up, and be ready to move to the next station.

Station 1: Sunlight.

Each student should point through the spectroscope directly at the sun, and draw the

component wavelengths observed. If weather permits, see if the colors are the same when

you are not looking through a window.

Station 2: Artificial light

Each student should point through the spectroscope directly at the fluorescent lights, and

draw the component wavelengths observed:

Station 3: Copper Chloride

Dip a paper clip into a copper chloride solution, and place it in the flame for less than two

seconds while your partner observes the emission of light through the spectroscope.

Repeat as necessary, but be cautious not to ignite the splint.

Station 4: Magnesium Combustion

Request a piece of magnesium metal from your instructor. Holding it in tongs, ignite the

magnesium and observe the spectrum through the spectroscope. Warning: The light is

extremely bright, and burns at 2000 degrees Celsius.

Station 5: Hydrogen gas

Turn on the hydrogen gas spectrum tube and observe the component wavelengths through

the spectroscope. You should see individual spectral lines.

Station 6: ______ Gas

Turn on the ________ gas spectrum tube and observe the component wavelengths

through the spectroscope. You should see individual spectral lines.

Data: Using colored markers, Draw what you see through the spectroscope as accurately

and precisely as you can. The marks are at 450, 550, and 650 nm.

1. Sunlight 2. Fluorescent Light

700

3. Copper Chloride

4. Magnesium combustion 5. Hydrogen Gas

700

6._______

_____________

_

400 500 600 700 400 500 600 700 400 500 600 700

400 500 600 700 400 500 600 700 400 500 600 700

Please answer the following questions at your normal seats:

1. Describe what you observed at each station:

1.

2.

3.

4.

5.

6.

2. Which light source provided the simplest spectrum?

3. Which light source provided the most complex or varied spectrum?

4. What were the wavelengths (in nanometers) of the individual lines from hydrogen in nanometers?

5. What were the colors of the individual lines from hydrogen?

6. Now that you have seen a variety of emission spectra, what do you believe causes the lines?

7(L1, honors only). Homework assignment: Research this topic, and explain where the observed lines

from the hydrogen emission spectrum come from. Your explanation should include a diagram, and the

application of the Balmer formula.

2

1

4

101097.0

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6C:

Hunds Rule: Electrons spread out within orbital groups

1s2 2s1

2p2X

1s2 2s2 2p2

1s2 2s2 2p6 3s2 3p4

16S:

3Li:

1s2 2s2

1s2 2s2 2p2

1s2 1s2

1s2 2s2 2p2

Ne Li Be Be

CNH O

X

Name_____________________________ Period_________ WS5.1

Wavelength Worksheet

Please show your work, not just the answer .

If you look down from Diamondhead in Hawaii, you will see waves rolling in at a steady rate. Some days

they are nicely spread apart, meaning they have a long wavelength. Other days they come in more

frequently; this is more dangerous for the surfers. The surfers prefer the long wavelength days. They

know that as the wavelengths get shorter, their frequency gets higher, and there is more energy- more

danger to the high frequency waves. This is summarized in the diagram:

Light travels in the same way. It travels at a steady rate: about 300,000,000 meters per second, or 3 x

108 m/s. And as the wavelength decreases, the frequency must increase:

Our eyes are really important to us, but they are kind of lame when you consider the tiny portion of light

from the electromagnetic spectrum that they can detect:

Wavelength Chart

We can use the wavelength formula and the chart on the previous page to understand things like radio

stations, visible light, and sunburns (due to ultraviolet light). Our ultimate goal is to make the connection

between light and the electron.

Wavelength Formula

S = wf S = speed of light = 3 x 108 m/s w = wavelength in meters (m) f = frequency in waves per second (Hz, or s-1)

In addition to a scientific calculator, you will need to refer to the wavelength chart on the previous page

to answer these questions.

1. An X-ray has a wavelength of 1.15 x 10-10 m. What is its frequency?

2. What is the speed and wavelength of an electromagnetic wave that has a frequency of 7.8 x 106 Hz?

3. A popular radio station broadcasts with a frequency of 94.7 megahertz (MHz). What is the

wavelength of the broadcast? (1 MHz = 1,000,000 Hz)

4. Cable television operates at a wavelength of about 1300 nanometers. What is the frequency of that

wave, and what region of the electromagnetic spectrum is it in? Is it dangerous? (Any wave more

frequent than visible light is considered dangerous).

5. Which is more dangerous, a radio wave or ultraviolet light?

6. The moon is 234,000 miles from earth. Light travels at 3 x 108 meters per second, and there are 1.62

kilometers in a mile.

When you shine a flashlight on the moon, how long does it take for the light to hit the moon?

7. The smallest particle of light is the photon. Max Planck discovered that the energy of light can be

calculated, where it is simply equal to a constant number multiplied by the frequency of the light:

What is the energy of a photon of green light?

(See question number 1)

8. What is the energy of a photon of light with a wavelength of 2 meters?

9. Since s = wf, and E = hf, can we calculate energy using wavelength, by combining the two formulas?

Please show the combined formula. (Hint: note that f appears in both formulas).

Light Energy Formula:

E = hf

Where E is the energy of the light in joules

h = Plancks Constant = 6.626 x 10-34 joules .seconds

f = the frequency of light in Hz (which is 1/seconds)

Example. What is the frequency of green light, which has a wavelength of 4.90 x 10- 7 m?

Solution: 1-147-

8

s 10 x 6.12 m 10 x 4.90

m/s 10 x 3

w

s f wf; s

Name____________________________ Period_______ WS5.2

The Bohr Model of the Atom

Prior to the work of Niels Bohr, it was known that electrons existed outside of the nucleus, but beyond

that very little was known.

1. What was the observation that Bohr based his research on?

2. The Balmer formula is :

Solve this formula for n = 4.

3. The heart of Bohrs discovery was that he was able to come up with real meaning to this formula. Draw

a hydrogen atom with several energy levels (shells) around it and show electronic emission from the

fourth shell to the second shell.

4. Draw diagrams indicating atomic emission and absorbance.

5. All of the visible atomic emissions for hydrogen enter the second energy level. What wavelength of

light is emitted when an electron moves from the second energy level to the first energy level?

What type of light is this?

22 n

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Name:_______________________________________ Period:______ WS5.3

Electron Configuration (L1 only)

Directions: Draw the electron configurations with orbital notation for each of the following atoms.

Example: Here is the electron configuration

of Sulfur with orbital notation.

1. Scandium:

2. Gallium:

3. Silver:

4. Krypton:

5. Iron:

6. Bromine:

7. Californium

8. Write the electron configuration using shorthand notation of the following elements:

a. sodium

1s2 2s2 2p2 3s2 3p4

16S:

b. An oxygen anion, O-

c. Radon

9. Two substances that have the same number of electrons are isoelectronic. For example, both the fluorine anion F- and neon have ten electrons, they are isoelectronic.

a. The bromine anion is isoelectronic with what uncharged element?

b. Argon is isoelectronic with which monocation?

b. An oxygen anion, O-

c. Radon

9. Two substances that have the same number of electrons are isoelectronic. For example, both the fluorine anion F- and neon have ten electrons, they are isoelectronic.

a. The bromine anion is isoelectronic with what uncharged element?

b. Argon is isoelectronic with which monocation?

Name___________________________________ Period __________________ WS 5.4

Electron Configuration NOT! Worksheet (L1 only)

In this unit we have seen how the electrons are organized around the nucleus. It is a very detailed view

of the electrons location, and various rules to help keep it all straight have been devised, and are shown

below.

In each problem below, the electron configuration is

incorrect. Fix it, and explain what law or principle (not

Principal!) was violated.

EXAMPLE:

1. 1Hydrogen:

2. 17Chlorine

3. 39Yttrium

(next page)

2s1

3s2 2p6 2s2 1s2

4d10 5s2 4p6 3d10 4s2

3p6 3s2 2p6 2s2 1s2

Unit 5 electrons Dr. B.s ChemAdventure

Principles and rules of electron configuration

Pauli

(opp. spins)

Hunds Rule

(spread out)

1s22s11s22p1Aufbau

(build up)

Heisenberg(e-position uncertain)

GoodBadPrinciple or rule

1s22s22p2 1s22s22p2

1s2 1s2

Law Violated:

Aufbau Principle

Fixed:

Law Violated: __________

Fixed:

1s1

3p5

4. 8Oxygen

5. 106Seaborgium

2s2 1s2 2p4

6d4 5f14 7s2 6p6 5d10

4f14 6s2 5p6 4d10

5s2 4p6 3d10 4s2

3p6 3s2 2p6 2s2 1s2

Laws Violated:

__________

Fixed:

Law Violated:

__________

Fixed:

Law Violated:

__________

Fixed:

Name:_______________________________________ Period:______ WS 5.5

Electron configuration and orbital notation self test

Chemical behavior is determined by electron position. Its a simple statement, but it says a lot. Another

way of saying it is Chemistry is all about where the electrons are.

Thats why weve been spending the last week focusing on electrons. However, somehow it always seems

to bog down in some weird world of 1s2 2s2 2p6, and the Pauli Principle, and we forget our goal: if we know

where the electrons are we know how the substance will behave. Why Neon is stable, and sodium is very

unstable, and in fact why all the elements and the substances they form behave the way they do.

Lets pick an element. We know that oxygen contains ___ protons. And since it is not charged, it contains

_____ electrons. We know that ____ of the electrons occupy the first shell, and the other six are in

the second shell. We know that the first shell consists of a _____ orbital that holds _____ electrons,

and so we say that the electron configuration of that first shell is 1s2. For the second shell we have six

electrons, and we have learned that the first two will occupy a ____ orbital, and the next four go into

____ orbitals. Thus the electron configuration of oxygen is____________________.

We can go into more detail, and show the exact orbitals that the electrons are in, which even show the

direction the electrons are spinning in. An atomic orbital is simply a ______ of electrons, and the Pauli

Principle tells us that electrons prefer to pair up with _________ spins. The first shell of oxygen

contains one orbital, which we draw with a box like this:_______, showing that the electrons are paired

up with opposite spins. The second shell begins with one more orbital for the two electrons of the 2s

subshell, for a total of four electrons so far. We have ______ more electrons in oxygen, and they will

occupy the three p orbitals. We remember to apply _________s rule and spread these electrons out as

far as possible in those three boxes. Thus we can draw the electron configuration of oxygen with its

orbital notation right above it:

Note that this tells us that oxygen has four electrons in its outer (second) shell, and the two of them

are unpaired.we also know from HONC that oxygen likes to form two bondsa coincidence??

Lets work out the electron configuration of nitrogen and see if we get three unpaired electrons:

Nitrogen has _____ electrons, so the electron configuration with orbital notation is (be sure to spread

out your p electrons):

Does this orbital notation show 3 unpaired electrons??

If this makes sense, continue to the how to ace it guide.. If not, see me so we can do more examples.

Howtoaceitunit5

How to ace the Electrons Exam

In this Unit our goal was to determine where the electrons are in atoms. To find out, we performed two

experiments that revealed the sharp lines that excited pure elements produced. We then analyzed this

data from a historical perspective, beginning with the work of Niels Bohr. For this we needed to review the properties of light, including frequency, wavelength, energy, and, common types. This involved the

use of the speed of light equation (s = wf) and an understanding of the electromagnetic spectrum. We

then showed how the key mathematical solutions of Balmer and Rydberg allowed Bohr to put it all together to postulate energy levels, where atomic emission explains light, and produces the spectral lines

observed for all elements.

This was followed by a detailed look at the electron around the nucleus. We found that not only do

electrons reside in shells, there are also subshells or orbitals within each shell. We observed how

they spread out within an orbital (Hunds Rule), and even how they spin when near each other (the Pauli Principle). We learned the configurations of electrons for all elements following the Aufbau Order, and how to write it all down by electron position, configuration, or orbital notation. This can rapidly tell us

how many electrons are in each shell and subshell, the spin of each electron, and the number of unpaired

electrons.

The limits of observation of the electron are a result of the Heisenberg Uncertainty Princliple, which

states that it is impossible to measure the position and velocity of an electron simultaneously, due to the

extreme sensitivity of the electron. Finally, we showed how valence is easy to determine using the periodic table, and that valence may be drawn using electron dot formulas, also known as Lewis Dot

Formulas.

During this study we found that the periodic table is well designed to show the number of valence

electrons for any element. In our next unit we will apply this to our understanding of the periodic table.

To dominate this test, review all of the material in his packet: The lessons, the labs, and the worksheets.

Here is some of the key information you should know:

To ace this exam you should know:

1. Draw the symbols for Democritus, Aristotle, Ghazali, Lavoisier, Dalton, Thomson, Rutherford, and

Bohr

2. What is the significance of each symbol? Try to assign one or two key words for each symbol.

3. What are the dangerous wavelengths of light?

4. How does light relate to electrons?

5. What is wavelength? Units?

6. What is frequency? Units?

7. Rearrange the speed of light equation to show what frequency is equal to.

8. The electromagnetic spectrum: what is it?

9. Frequency: how does it relate to energy and safety?

10. Wavelength- how does it relate to frequency?

11. Energy: which rays have the highest energy?

12. Safety: why are radio waves generally considered safe?

13. Types of radiation

Really long waves include ___________ and _______________; really short waves

include __________ and ____________. The ___________________ (long/short)

waves are dangerous.

14. Convert 452 nanometers to meters (107 nm = 1m)

15. Use s = wf to find the frequency of 452 nm light.

16. (Level one only) The Balmer formula. Find it in your notes:

17. Significance

18. Solve for the n= 3 to n = 2 transition:

19. Atomic Emission Spectra: How did we observe it?

20. Emission vs. absorbance- what is the difference?

21. The Bohr model of the atom- draw a model

21.5 What is the difference between electron configuration, and orbital notation?

22. Electron names to zirconium. For example, manganese has the symbol ____

23. L1 only: Electron configurations- all elementsdo iodine using noble gas notation.

24. L1 only: Orbital notation: all elements. Do silicon. Include the number of valence electrons, and the

number of unpaired electrons.

25. The Heisenberg Uncertainty Principle. State what it is and why briefly.

26. L1 only: Orbitals: s, p, d, and fhow many electrons for each? How many orbitals for each?

27. L1 only: Aufbau principle. Give an example where it is broken, and fix it.

28. L1 only: Pauli exclusion principle. Break it and fix it.

29. L1 only: Hunds Rule. Break it and fix it.

30. Lewis Dot Structures. Draw oxygen, for example

31. Valence Electrons. Do each column in the periodic table..

32. Why is it important to use scientific references, rather than websites, when writing a scientific

paper?

33. Where are the electrons in an atom?

The Periodic Table

Unit 6

Introduction

The universe is composed of approximately 120 elements. These are pure substances with a fixed

number of protons: hydrogen has 1, helium 2, carbon 6 etc.

They could be listed in a few rows:

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49

50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93

94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120

But that wouldnt really tell us much.

Or maybe they could be organized another way, since for example 5 x 4 x 3 x2 x 1 = 120 but would

there be a reason for organizing it that way?

If the universe only has about 120 elements, it seems reasonable to expect some sort of organization

to them. That is what the periodic table is about: trying to figure out how the most basic matter in the

universe is organized.

But theres a problem. The periodic table just

doesnt look right. Here it is below:

An important concept in science is known as

Occams Razor, which suggests that the simplest

answer tends to be the right one.

In the table on the left most rows and columns are

of different length, and it is in two pieces. This is

not a simple table. Could it be that we humans just havent figured it out yet? Im hoping you can do

better. Somebody should.

What is the periodic table good for?

Our Essential Question:

OO

OOH

O OH

OO

O

O

O

O

OH

NHO H

1. taxol (paclitaxel)


I

r r r r r r r r r

Name___________________ Period__________ Lab7.4

Salt Adventure Lab 20 Points

Introduction: Ionic compounds are everywhere. Sometimes simply called salts, we add them to food (sodium chloride), enhance our food (monosodium glutamate,

or MSG), preserve our food (sodium benzoate), or we may even take a bath in

them (magnesium sulfate, or Epsom salts.) Ionic compounds are substances that

contain a cationic metal (M+) bonded to an anionic nonmetal (NM-). NaCl, for

example, is an ionic compound.

In this lab our goals are to explore the physical and chemical behavior of these salts. Are they

reactive? Are they soluble in water? Can we predict the products of a reaction? Do the individual

ions show trends in terms of solubility or color?

Procedure:

1. We have about 7 different types of dissolved salts, and wed like to perform every possible

individual chemical reaction- this is known as a combinatorial array. Create a 7 x7 grid below to record your observations. Use the symbols C (color change), P (precipitate), O (outgassing)

or NR (no reaction) to record your results.

1.

______

2.

______

3.

______

4.

______

5.

______

6.

______

7.

______

1.

________

2.

________

3.

________

4.

________

5.

________

6.

________

7.

________

C = color change, P = precipitate, O = outgassing, NR = no reaction

How many possible reactions are there?. __________

Note: These salts are toxic. Wear safety glasses and work carefully.

Once you have completed your array, clean up completely and get your

paper stamped, then answer the questions on the back.

Clean-up

stamp

I

1. ______

2. ______

3. ______

4. ______

5. ______

6. ______

7. ______

1. ________2. ________3. ________4. ________5. ________6. ________7. ________

W

Winvestment x price original

price new estock valu

Name_________________________________ Period_________ Lab 7.1

Pharmacetical Stock Project

Want to make a million dollars? This week is your chance. Well, at least on paper. Here is how it works:

One of the best places to make (or lose, especially now) serious money is in the stock market. You invest money in a company, and if the stock value of that company goes up,

you make money.

Example: You purchase 1000 dollars worth of Google stock. On the day you buy it each share is worth 485 dollars. One month later the stock is selling at 560 dollars per share-

its value has increase by 15%. You have just made a quick 150 dollars on your investment. In other words,

investment x price original

price new estock valu

Each student is given one million dollars. You will invest it in any two of the following Pharmaceutical Companies.

Research these companies tonight and choose your investments. For example, you may put $700,000 into Amgen, and the rest ($300,000) into NPS. All student will be

responsible for knowing the basics of each company. On the following page is a chart for keeping track of your stocks

Become a millionaire project: Chart Name________________________ lab 7.1

On this page list your 2 stock choices and investments totaling one million dollars. For example, you

may choose to invest $220,000 in Pfizer, and $780,000 in Bristol-Meyers Squibb. If you make money

between now and December 23 you earn one bonus point on the Bonding Test; the biggest money

winner gets extra points (varies by class).

Stock #1:______________ Investment: $_____________Todays Trading Price:____________

Stock #2:______________ Investment: $_____________Todays Trading Price:____________

Date Stock #1:

_______

Trading

Price Today

Stock #1

Current

value

Stock #2:

_______

Trading

Price Today

Stock

#2

Current

value

Total

Value

I have made

(+) or lost (-)

this much:

LAST DAY: Wed, Dec. 23 Final Value: In this project I made/lost $______________

Sample calculation: You invest half a million dollars in Covidien and the stock increased from 20 to 21.

Current value = new price/ original price x investment

= 21/20 x $500,000 = $525,000.

You just made 25,000 dollars. Go buy a new car.

O

Name____________________________________Period___________Date_______ lab7.3

Make a Huge Molecule Project 20 Points

Introduction: Organic molecules have incredibly complex and varied structures. Simple plants can

produce them naturally, yet it takes people literally years to make them in the lab.

Shown below are some examples of complex, large natural products from plants.

OO

OOH

O OH

OO

O

O

O

O

OH

NHO H


O

OOH

H

OO

OH

H

H

O

O

OOO

O

O

O

O

OH

H

H

azadirachtin

Co3+

N

N

N

N

N

R

N

O

NO

NO

N

O

O

N O

N O

N

O

N O

O

O

PO

O

O

3. Vitamin B12

O

O

O

OH

OH

OH

OH

OH

OH

OH

H

H

O

OH

H

H

H

H

O

O

O

OHOH

OH

OH

OH

OH

O

4. ginsenoside rb2

I

OO

OOH

O OH

OO

O

O

O

O

OH

NHO H


O

OOH

H

OO

OH

H

H

O

O

OOO

O

O

O

O

OH

H

H

azadirachtin

Co3+

N

N

N

N

N

R

N

O

NO

NO

N

O

O

N O

N O

N

O

N O

O

O

PO

O

O

3. Vitamin B12

O

O

O

OH

OH

OH

OH

OH

OH

OH

H

H

O

OH

H

H

H

H

O

O

O

OHOH

OH

OH

OH

OH

O

4. ginsenoside rb2

OH

OOH

OH

OH

S

O

OO

O

O

O

O

O

O

OH

OHOH

OH

OHOH

OH

O

O

O

O

O

O S

O

OO

OH

OH

OH

OHO

O

O

O

OHOH

OH

OH

OH

O O

OO

O

O

O

OH

OH

O

O

O

OO

O

O

O

O

O

OH

OH

OH

OH

OH

OH

H

H

H

H

HH

H

H

H

H

H

H

H

H

H

H

H

H

H

H

H

H

H

H

H

H

H

H

H

H

H

H

HH

H

H

H

H

H

H

H

H

H

H H

H

H

H

H

Na

Na

I

Lithium Beryllium Boron fluoride permanganateoxide

Sodium MagnesiumAluminum bromide bicarbonate sulfide

Potassium Calcium Chloride hypochlorite chromate

Rubidium Strontium iodide chlorite dichromate

Cesium Barium chlorate

Francium Radium nitrite perchloratecarbonate

Ammonium Zinc nitrate bromate sulfite nitride

silver bisulfateiodate

sulfate phosphide

hydroxide acetate

cyanide phosphate

M

NSi

O

ONa

O

H

Br

F Li

+

+2 +3 -3 -2 -1

polyvalent

+1 0

N

H-O-H

Si NCl

N N

G

NH

H H

H

H

H

H

N H

H

H

H H

H H

C Cand C

C

D

UO OO+

-

Cr r r r


W

r r r r r r r r r

Name:__________________________________ Period:______ lab 8.1

Evidence for a Chemical Change

(10 Points)

Purpose: To observe a sequence of changes that occur when a solution of copper (II) nitrate is

treated with a series of different reactants. All the reactions occur in the same test tube. At each

step you will look for evidence that a new substance is formed.

Safety: Wear gloves, goggles and aprons.

Materials:

- 1 Test Tube - Bunsen Burner - Ring Stand

- Aluminum Foil - 100 mL Beaker - Crucible Tongs

- Ruler - Glass Stirring Rod - Wire Gauze

- Evaporating Dish - Cooper (II) Nitrate - Sodium Hydroxide

- 1.5 M HCl

Procedure:

Four reactions will take place in one test tube.

1. Perform the first reaction by adding CuNO3 and NaOH to a test tube.

What signs were there of a chemical reaction?

2. Keep this first product from this reaction and heat the test tube in hot water to produce a second

product.


3. Keep the second product and add HCl to form a third product.


4. Keep the third product and add a rolled strip of Aluminum Foil to form the final product.


Please clean up and have your instructor sign off:

Answer the questions on the other side of this paper at your desk.

Name:___________________________________ Period:______ lab 8.2

Types of Chemical Reactions

(10 Points)

Purpose: To learn to differentiate among the five general types of Chemical

Reactions.

Safety: Wear gloves, goggles and aprons.

Materials:

- 5 Test Tubes - Bunsen Burner - Dropper Pipet -

Tongs

- Iron Filings - 0.1 M CuSO4 Solution - 0.1 M Fe(NO3)3 Solution

- 0.1 M KI Solution - CuSO4 5 H2O - Mg Ribbon

- 6M HCl - 3% H2O2

Procedure:

Part 1: Iron Metal and Copper (II) Sulfate Solution:

1. Fill a test tube full of Copper (II) Sulfate Solution.

2. Add approximately 2 g of Iron Filings to the Solution.

3. Observe the Reaction for 5 minutes.

4. Discard the Contents and clean the test tube.

5. The two new substances are Iron (II) Sulfate and Copper.

What did you observe? ____________________________________________________

___________________________________________________________________

How do you know a chemical change occurred? _________________________________

Write a balanced chemical equation for the reaction you performed:

___________________________________________________________________

What type of reaction was this? ______________________________________________

Part 2: Iron (III) Nitrate and Potassium Iodide Solution

1. Put 2 mL of Iron (III) nitrate solution in a test tube.

2. Add 5-10 drops of Potassium Iodide solution.

3. Observe the Reaction that has occurred.

4. Discard the contents and clean the test tube.

5. The two new substances are Iron (III) Iodide and Potassium Nitrate.

1Chemical Reactions

Sign

s2

. Wh

at t

hey

are

no

t

Writing chemical reactions 5 types Solvents are your friends

A p

eek at acids an

d b

ases

The Hindenberg Zeppelin Reactions of alkali metals

The four COOL signs of a chemical change are:1. Color

2. Odor3. Outgassing

4. Loweror higher temperature

A process where New Substances are formed;

New Chemical Bonds are made.

1The reaction is balanced

2

Water can be easily decomposed into the elements.

Write a word equation for this process:

2 Hints:

1. Dont forget about diatomic molecules (HBrONClIF)

2. Include the state (s, l, g, or aq) for each substance

Water Hydrogen + Oxygen

OK, now write a balanced chemical equation:

H2O (l) H2 (g) + O2 (g)

Draw a line in front of each substance and balance it:

The number of each element must be equal for

Reactants and products.

____ __2 (1)

Watch each reaction, write a balanced chemical equatio, and describe

the reaction type:

Going deeper: not all reactions fit into these categories (esterification,

for example.

1Write a balanced chemical equation for:

1. The reaction of sodium chloride and magnesium

bromide:

2. The combustion of methane (CH4):

3. The decomposition of methanol CH4O) into carbon,

hydrogen, and oxygen:

NaCl + MgBr2 NaBr + MgCl22 2(1) (1)

CH4 + O2 CO2 + H2O2 2(1) (1)

CH4O C + H2 + O22 2 (1)

Hint: Do hard elements (O) last

24

How do we avoid wasting reactants if they are too small to count?

My answer: expert answer

Watch the video and ask yourself if both reactants are fully consumed

(did they waste anything?)

My answer: expert answer

Some relative masses

Relative mass in grams = Molar mass

1What kind of chemical reaction is it? The 5 types.

1. Synthesis

A + B AB

2. Combustion

(combining with oxygen)

3. Decomposition

AB A + B

4. Replacement

A + BX AX + B

5. Double Replacement

AX + BY AY + BX

(Hooking up)

(Burning)

(Breaking up)

(switching)

(Double-switch)

1The reaction is balanced

2

Water can be easily decomposed into the elements.

Write a word equation for this process:

2 Hints:

1. Dont forget about diatomic molecules (HBrONClIF)

2. Include the state (s, l, g, or aq) for each substance

Water Hydrogen + Oxygen

OK, now write a balanced chemical equation:

H2O (l) H2 (g) + O2 (g)

Draw a line in front of each substance and balance it:

The number of each element must be equal for

Reactants and products.

____ __2 (1)

Watch the reaction, then provide a one mole scale recipe

1Name that reaction type

AB A + B

Decomposition

AX + BY AY + BX

Double replacement

A + B AB

Synthesis

H2 + 02 H20

Comb

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chemistryadventure test 1.25.2011