Mad Science Homeschool Productions

Lab Manual

for Illustrated Guide to Home Chemistry

Elizabeth Moore

3/29/2011

Honors level high school chemistry laboratory manual produced by and used in our home school, Renaissance Classical Academy.

Table of ContentsRequired Materials......................................................................................................................................1

Required Book.........................................................................................................................................1

Safety Equipment....................................................................................................................................1

Other Suggested Books and Materials.....................................................................................................1

Lab Session Procedures...............................................................................................................................1

Before the First Lab Session.....................................................................................................................1

Before Each Lab Session..........................................................................................................................2

Lab Safety....................................................................................................................................................3

General Chemistry Lab Safety..................................................................................................................3

Attire....................................................................................................................................................4

Conduct...............................................................................................................................................4

Proper Handling of Chemicals and Equipment....................................................................................4

Safety Exams:..........................................................................................................................................5

Materials Data Sheets:............................................................................................................................5

Lab Experiments..........................................................................................................................................6

Week 1: 6.1 Differential Solubility: Separate Sugar and Sand..................................................................6

Mixtures..............................................................................................................................................6

Differing Solubilities.............................................................................................................................6

Week 2: 6.2 Distillation; Purify Ethanol...................................................................................................7

Distillation............................................................................................................................................7

Week 3: 6.3 Recrystallization: Purify Copper Sulfate...............................................................................8

Crystallization......................................................................................................................................8

How to do a crystallization..................................................................................................................8

Week 4: 6.4 Solvent Extraction................................................................................................................9

Extraction in the chemistry teaching labs............................................................................................9

How to do an extraction......................................................................................................................9

Week 5: 6.5 Chromatography: Two-Phase Separation of Mixtures.......................................................11

Chromatography................................................................................................................................11

Weeks 1-5 Summary..........................................................................................................................13

Week 6: Solutions of Solid Chemicals....................................................................................................14

7.1 Make Up a Molar Solution of a Solid Chemical............................................................................14

7.2 Make Up a Molal Solution of a Solid Chemical............................................................................14

Week 7: Solution of Liquid Chemicals and Mass-to-Volume Percentage..............................................14

7.3 Make Up a Molar Solution of a Liquid Chemical..........................................................................14

7.4 Make Up a Mass-to-Volume Percentage Solution.......................................................................14

Week 8: Colligative Properties of Solutions...........................................................................................14

8.1 Determine Molar Mass by Boiling Point Elevation.......................................................................14

8.2 Determine Molar Mass by Freezing Point Depression.................................................................14

8.3 Observe the Effects of Osmotic Pressure.....................................................................................14

Week 9: 9.2 Observe a Decomposition Reaction...................................................................................14

9.1 is skipped as impractical due to smell and toxicity......................................................................14

Week 10: 9.3 Observe a Single-Displacement Reaction........................................................................14

Week 11: 9.4 Stoichiometry of a Double Displacement Reaction..........................................................14

Week 12: 10.1 Reduction of Copper Ore to Copper Metal....................................................................14

Week 13: 10.2 Observe the Oxidation States of Manganese.................................................................14

Week 14: 11.1 Determine the Effects of Concentration on pH..............................................................14

Week 15: 11.2: Determine the pH of Aqueous Salt Solutions................................................................14

Week 16: 11.3 Observe the Characteristics of a Buffer Solution...........................................................14

Week 17: 11.4 Standardize Hydrochloric Acid Solution by Titration.....................................................14

Week 18: Determine Effects of Temperature and Surface Area on Reaction Rate................................14

12.1 Determine the Effects of Temperature on Reaction Rate..........................................................14

12.2 Determine the Effects of Surface Area on Reaction Rate...........................................................14

Week 19: 12.3 Determine the Effects of Concentration on Reaction Rate............................................14

Week 20: 13.1 Observe Le Chatelier's Principle in Action.....................................................................14

Week 21: 13.2 Quantify the Common Ion Effect...................................................................................15

Week 22: 14.1 Observe the Volume-Pressure Relationship of Gasses (Boyle's Law).............................15

Week 23: 14.2 Observe the Volume-Temperature Relationship of Gasses (Charles's Law)..................15

Week 24: 14.3 Observe the Pressure -Temperature Relationship of Gases (Gay-Lussac's Law)............15

Week 25: 14.4 Use the Ideal Gas Law to Determine the percentage of Acetic Acid in Vinegar.............15

Week 26: 15.1 Determine Heat of Solution...........................................................................................15

Week 27: 15.2 Determine the Specific Heat of Ice................................................................................15

Week 28: 15.3 Determine the Specific Heat of a Metal.........................................................................15

Week 29: 16.1 Produce Hydrogen and Oxygen by Electrolysis of Water...............................................15

Week 30: 18.1 Observe Some Properties of Colloids and Suspensions.................................................15

Week 31: 18.2 Produce Firefighting Foam.............................................................................................15

Week 32: 18.3 Prepare a Gelled Sol.......................................................................................................15

Week 33: Discriminate Metal Ions.........................................................................................................15

19.1 Using Flame Tests to Discriminate Metal Ions...........................................................................15

19.2 Using Borax Bead Tests to Discriminate Metal Ions...................................................................15

Week 34: 20.1 Quantitative Analysis of Vitamin C by Acid-Base Titration.............................................15

Week 35: 20.2 Quantitative Analysis of Chlorine Bleach by Redox Titration.........................................15

Week 36: 21.1 Synthesize Methyl Salicylate from Aspirin.....................................................................15

Lab Manual for Illustrated Guide to Home Chemistry

Required Materials

Required BookIllustrated Guide to Home Chemistry Experiments by Robert Bruce Thompson. (O’Reilly, 2008)

Safety EquipmentFor EACH student, supervising or observing parent, and observing sibling:

Splash GogglesVinyl Lab Apron (or chemical resistant lab coat)Chemical resistant safety gloves

(These materials are available from http://www.hometrainingtools.com inexpensively.)

Other Suggested Books and MaterialsSuccessful Lab Reports: A Manual for Science Students by Christopher S. Lobban, MarLa Schefter (Cambridge University Press, 1993) Note: available used inexpensively from Amazon.com

Chemistry Problem Solver (Problem Solvers) by A. Lamont Tyler (REA, 2008) Note: While not required, this may help with math associated with several of the labs. Relevant problems are listed for labs involving math or math-like problem solving in the reading section. Each problem should be copied out on paper and attempted before checking the solution and moving to the next problem.

The McGraw-Hill Dictionary of Chemistry online at http://survival-training.info/Library/Chemistry/Chemistry%20-%20MCGraw-Hill%20Osborne%20Dictionary%20of%20Chemistry%20-%20Unknown.pdf

Hardbound Quad Ruled Lab Notebook for each student in the class

Scientific calculator (We like the TI-30XS, but any scientific calculator will work.)

Uncle Tungsten: Memories of a Chemical Boyhood by Oliver Sacks (Unassigned individual reading or family read-aloud. Neuroscientist Oliver Sachs recalls his childhood, back in the days when drug stores sold chemicals to inquiring boys. He has great stories of his experiments (and explosions) in his backyard "lab".)

Lab Session Procedures

Before the First Lab SessionFamiliarize yourself with the style of this lab manual. Each week and/or experiment begins with any required reading in the lab text, Illustrated Guide to Home Chemistry, and suggested readings in other texts followed by a short explanation of the theory or techniques to be used in the lab. The explanations in this lab manual may be read prior to the text readings if desired. The lab itself is not specifically assigned, but must also be read prior to the lab session. Take special note of warnings and hazards associated with the lab and any chemicals used or created in the process, as well as disposal instructions. Safety equipment should be worn by all participants and observers in the labs at all times, and contact lenses should not be worn during lab sessions.

Read the Lab Safety section of this manual prior to the first lab session in addition to familiarizing yourself with the lab to be performed. Suggestions for lab safety quizzes are at the end of that section.

Before Each Lab SessionReview lab safety procedures. Read the section of this manual for the planned lab session and all assigned readings in that section as well as the lab itself. Prepare a flow chart of the lab. Perform all calculations needed prior to the start of the lab, such as quantities of particular compounds needed to create solutions of specified concentrations. One student may be assigned to prepare a flowchart, discussion, and safety information for each planned lab in the session to present to the group prior to beginning the lab. This presentation should not take more than 5-10 minutes. However, each student should be familiar with the lab procedures and warnings for all labs planned for the day prior to the start of the session.

It is strongly suggested that students key word outline the discussion of the technique and brief overview of theory prior to the lab and use that to write a rough draft of the Introduction section of their lab report directly into their lab notebook as part of their pre-lab preparation. This will also greatly speed up completion of lab reports if they are assigned by the student’s instructor.

Any pre-lab problems should also be completed prior to the lab. Suggested problems are provided to ensure student proficiency with quantitative methods used in the lab. In some cases worksheets may be provided in the manual. These should be done after the problems assigned. Answers for worksheets are in the back of this manual. Good pre-lab preparation and fast turnover of lab reports are good habits to establish for students intending to major in science or engineering in college.

Lab SafetyRead: "Keeping a Laboratory Notebook” pp 5-8

Chapter 2: Laboratory Safety

General Chemistry Lab Safety

The chemistry laboratory can be a place of discovery and learning. However, by the very nature of laboratory work, it can be a place of danger if proper common-sense precautions aren't taken. While every effort has been made to eliminate the use of explosive, highly toxic, and carcinogenic substances from the experiments which you will perform, there is a certain unavoidable hazard associated with the use of a variety of chemicals and glassware. You are expected to learn and adhere to the following general safety guidelines to ensure a safe laboratory environment for both yourself and the people you may be working near. Additional safety precautions will be announced in class prior to experiments where a potential danger exists. Students who fail to follow all safety rules may endanger themselves, their siblings, their parent instructors, and the laboratory space in which we are working.

Attire Safety goggles must be worn at all times while in the laboratory. This rule must be followed

whether you are actually working on an experiment or simply writing in your lab notebook while chemicals and equipment are unpacked in the space.

Contact lenses are not allowed. Even when worn under safety goggles, various fumes may accumulate under the lens and cause serious injuries or blindness.

Closed toe shoes and long pants must be worn in the lab. Sandals and shorts are not allowed. Lab aprons must be worn at all times. Old T-shirts are suggested as dedicated labwear underneath lab aprons.

Chemical resistant lab gloves must be worn when working with or observing experiments involving hazardous chemicals.

Long hair must be tied back at all times in the laboratory space, especially when using open flames.

Conduct Eating or drinking are strictly prohibited in the laboratory space while it is in use or has open

chemical bottles in it even if the kitchen is doubling as laboratory space. Keep food and beverages covered and put away during lab activities and until after the lab space has been thoroughly cleaned up and lab materials put away.

No handstands, cartwheels, mock fighting, or physical joking around of any kind is permitted in the lab.

No unauthorized experiments are to be performed. If you are curious about trying a procedure not covered in the experimental procedure, consult with your laboratory instructor.

Never taste anything. Never smell anything unless instructed to do so. Never directly smell the source of any vapor or gas; instead by means of your cupped hand, waft a small sample to your nose and ONLY when instructed to do so. Do not inhale these vapors but take in only enough to detect an odor if one exists.

Coats, backpacks, etc., should not be left on the lab surfaces or nearby floors. Put these safely in another room. Make sure no tripping hazards are in the lab space or exits from the lab space. Beware that lab chemicals can destroy personal possessions.

Always wash your hands before leaving lab, even just to go to the bathroom. Learn where the safety and first-aid equipment is located. This includes fire extinguishers, fire

blankets, and eye-wash stations. Notify the instructor immediately in case of an accident.

Proper Handling of Chemicals and Equipment Consider all chemicals to be hazardous unless you are instructed otherwise. Material Safety Data

Sheets (MSDS) are available in lab or via internet for all chemicals in use. These will inform you of any hazards and precautions of which you should be aware.

Never pipette by mouth. Know what chemicals you are using. Carefully read the label twice before taking anything from a

bottle. Chemicals in the lab are marked with NFPA hazardous materials diamond labels. Learn

how to interpret these labels. Appropriately label any stock solutions made during lab or pre-lab exercises.

Excess reagents are never to be returned to stock bottles. If you take too much, dispose of the excess.

Many common reagents, for example, alcohols and acetone, are highly flammable. Do not use them anywhere near open flames.

Always pour acids into water. If you pour water into acid, the heat of reaction will cause the water to explode into steam, sometimes violently, and the acid will splatter.

If chemicals come into contact with your skin or eyes, flush immediately with copious amounts of water and consult with your instructor.

Never point a test tube or any vessel that you are heating at yourself or your neighbor--it may erupt like a geyser.

Dispose of chemicals properly. Follow instructions in our lab manual for disposal of waste and chemicals used in the lab under adult supervision.

Clean up all broken glassware immediately and dispose of the broken glass properly with adult assistance and supervision.

Consult with instructor for clean-up of any chemical spills. Some spills, such as acids, should be neutralized prior to wipe up and disposal.

Never leave burners unattended. Turn them off whenever you leave your workstation. Be sure that the gas is shut off at the bench rack when you leave the lab.

Beware of hot glass--it looks exactly like cold glass.

Adapted from: http://chemlabs.uoregon.edu/Safety/GeneralInstructions.html

Safety Exams: http://www.flinnsci.com/Documents/miscPDFs/Safety_exam_HS.pdf http://www.sciencebyjones.com/lab_safety_quiz.htm

Materials Data Sheets: http://www.flinnsci.com/search_MSDS.asp

Lab Experiments

Introduction to Lab Weeks 1-5: Techniques for Separating MixturesThe first group of labs, 6.1 – 6.5, familiarizes students with basic laboratory techniques to separate mixtures. Students are not expected to have detailed knowledge of the theory behind these techniques, nor are involved quantitative methods required. Background knowledge from previous general, physical, and biological sciences classes will be sufficient for students to understand the main points of why each method is successful for separating certain kinds of mixtures. Younger siblings observing can be expected to follow along sufficiently to appreciate larger scientific principles and laboratory techniques involved.

Week 1: 6.1 Differential Solubility: Separate Sugar and SandRead: "Separating Mixtures” p 93

“Using a Balance” p 73“Filtration” pp 83-84“Using Heat Sources” pp 85-88

Successful Lab Reports: Part I: Writing the First Draft: Format (pp 1-49)

MixturesMixtures occur very commonly in chemistry. When a new substance is synthesized, for example, the new substance usually must be separated from various side-products, catalysts, and any excess reagent still present. When a substance must be isolated from a natural biological source, the substance of interest I generally found in a very complex mixture with many other substances, all of which must be removed. Chemists have developed a series of standard methods for the separation of mixtures. In fact, the separation of mixtures into their constituent substances defines an entire sub-field of chemistry referred to as separation science.

Differing SolubilitiesMixtures of solids may often be separated on the basis of differences in their solubilities. If one component of the mixture is soluble in water while the other components are insoluble in water, the water-soluble component can be removed from the mixture by dissolving the mixture in water and filtering the mixture through filter paper. The component dissolved in water will pass through the filter while the undissolved solids will be caught in the filter. Since the solubility of substances is greatly influenced by temperature, it may also be possible to separate the components by controlling the temperature at which the solution occurs or at which the filtration is performed. Often times, a sample is added to water and heated to boiling. The hot sample is then filtered to remove completely insoluble substances. The sample is then cooled to room temperature or below, which causes crystallization of those substances whose solubilities are very temperature dependent. These crystals can then be separated by another filtration, and the filtrate (the material that went through the filter) will then contain only those substances whose solubilities are not as temperature dependent.

(From CK12 Chemistry 2nd Edition p 408)

Define the following words in your lab notebook. Use the glossary in your Chemistry theory text or a resource such as the McGraw-Hill Dictionary of Chemistry.

dissolve solution

soluble solubility

Week 2: 6.2 Distillation; Purify EthanolRead: “Measuring Liquids By Volume” pp 74-78 (Burette's will be covered later.)

“Using Heat Sources” p85-88"

DistillationHomogeneous solutions are most commonly separated by distillation. In general, distillation involves heating a liquid to its boiling point, then collecting, cooling, and condensing the vapor produced into a separate container. A common distillation setup is illustrated to the right.

In solutions of non-volatile (resistant to vaporization) solid solutes in liquid solvent, when the solution is boiled, only the solvent boils off and all of the solid remains in the solution. As the solvent vaporizes and all of the solute remains behind, the same amount of solute is now dissolved in less solvent. Since the concentration increases, the boiling point of the solution is also increasing. As the solution boils, increased temperature is necessary to keep the solution boiling because its boiling point has increased. This is a quick method of determining if a liquid is a pure substance or a solution: start boiling the solution, and if it continues to boil at the same temperature, it is a pure substance, whereas if its boiling point increases, it is a solution.

For a mixture of liquids in which several components of the mixture are likely to be volatile (easily vaporized), the separation is not as easy. If the components of the mixture differ reasonably in their boiling points, it may be possible to separate the mixture simply by monitoring the temperature of the vapor produced as the mixture is heated. Liquid components of a mixture will each boil in turn as the temperature is gradually increased, with a sharp rise in the temperature of the vapor being distilled indicating when a new component of the mixture has begun to boil. By changing the receiving flask at the correct moment, a separation can be accomplished. This process is known as fractional distillation. (From CK12 Chemistry 2nd Edition pp 408-409)

Define the following words in your lab notebook. Use the glossary in your Chemistry theory text or a resource such as the McGraw-Hill Dictionary of Chemistry.

solute solvent volatile

distillation distillate

Week 3: 6.3 Recrystallization: Purify Copper SulfateRead: “Using a Balance” p 73

“Filtration” pp 83-84“Using Heat Sources” p85-88

CrystallizationCrystallization is a technique which chemists use to purify solid compounds. It is one of the fundamental procedures each chemist must master to become proficient in the laboratory. Crystallization is based on the principles of solubility: compounds (solutes) tend to be more soluble in hot liquids (solvents) than they are in cold liquids. If a saturated hot solution is allowed to cool, the solute is no longer soluble in the solvent and forms crystals of pure compound. Impurities are excluded from the growing crystals and the pure solid crystals can be separated from the dissolved impurities by filtration.

This simplified scientific description of crystallization does not give a realistic picture of how the process is accomplished in the laboratory. Rather, successful crystallization relies on a blend of science and art; its success depends more on experimentation, observation, imagination, and skill than on mathematical and physical predictions. Understanding the process of crystallization in itself will not make a student a master crystallizer, rather, this understanding must be combined with laboratory practice to gain proficiency in this technique.

How to do a crystallizationTo crystallize an impure, solid compound, add just enough hot solvent is added to it to completely dissolve it. The flask then contains a hot solution, in which solute molecules – both the desired compound and impurities – move freely among the hot solvent molecules. As the solution cools, the solvent can no longer “hold” all of the solute molecules, and they begin to leave the solution and form solid crystals. During this cooling, each solute molecule in turn approaches a growing crystal and rests on the crystal surface. If the geometry of the molecule fits that of the crystal, it will be more likely to remain on the crystal than it is to go back into the solution. Therefore, each growing crystal consists of only one type of molecule, the solute. After the solution has come to room temperature, it is carefully set in an ice bath to complete the crystallization process. The chilled solution is then filtered to isolate the pure crystals and the crystals are rinsed with chilled solvent.

Detailed photos from start to finish: http://orgchem.colorado.edu/hndbksupport/cryst/crystproc.html

Crystallization Movie: http://video.google.com/videoplay?docid=5617753349611003526 On GoogleVideo - choose "smoothing" and "original size" from the lower right pull-down menu for best video.

Source: http://orgchem.colorado.edu/hndbksupport/cryst/cryst.html on March 22, 2011

Define the following word in your lab notebook. Use the glossary in your Chemistry theory text or a resource such as the McGraw-Hill Dictionary of Chemistry.

recrystallization

Week 4: 6.4 Solvent ExtractionRead: "Separations" pp 84-85

Extraction in the chemistry teaching labsLiquid-liquid extractions using a separatory funnel are essentially the only kind of extraction performed in the most chemistry teaching labs. The "liquid-liquid" phrase means that two liquids are mixed in the extraction procedure. The liquids must be immiscible: this means that they will form two layers when mixed together, like oil and vinegar do in dressing. (A demonstration of this fact using red wine or balsamic vinegar and oil may be useful for students and/or younger siblings.) Some compounds are more soluble in the organic layer (the "oil") and some compounds are more soluble in the aqueous layer (the "vinegar"). Recall last year’s discussion in Biology of lipid bilayers in cell membranes and cell membrane permeability.

The photo at the right illustrates how two liquid layers separate. The red layer is simply red food coloring in water. Water is immiscible with the other liquid, which is methylene chloride. Methylene chloride is heavier (denser) than water, therefore, the clear methylene chloride layer is under the red, aqueous food coloring layer.

Quiz: Red food coloring is soluble in water and not in methylene chloride or diethyl ether. The photo at the right illustrates what you see if you mix methylene chloride, water, and red food coloring and allow the layers to separate. What would you expect to see if you mixed diethyl ether, water, and red food coloring? Go to the next page for the answer.

In a particular experiment in simple extraction or in chemically active extraction, you will be able to figure out which layer, aqueous or organic, will contain the compound you want to isolate. You will also need to know which layer will be on top in the separatory funnel. This is determined by the density of the two solvents. Densities are listed in various sources of scientific data, as referenced on the Chem Info page on this orgchem site:

Hazard and Physical Data for Compounds: http://orgchem.colorado.edu/cheminfo/cheminfo.html

How can you determine the density of a solvent you are working with if you did not have access to sources of scientific data?

How to do an extractionExtraction Procedure (separatory funnel): http://orgchem.colorado.edu/hndbksupport/ext/extprocedure.html

Extraction Movie: http://video.google.com/videoplay?docid=945061828857075635&hl=en On GoogleVideo - choose "smoothing" and "original size" from the lower right pull-down menu for best video.

As we do not have a separatory funnel, we will be following adapted procedures that will not allow quite as good a separation. Please see The Illustrated Guide to Home Chemistry for procedures we will use.

Quiz Answer: In order to make a prediction as to which layer is on the top and which on the bottom, you need to know the densities. The following data is from the Tables in the Handbook:

diethyl ether d = 0.71

methylene chloride d = 1.33

water d = 1.00

Therefore, if you mix diethyl ether, water, and red food coloring, shake it in a sep funnel and allow the layers to separate, it will look like the mixture in the sep funnel on the left in the photo below (big yellow check mark). The food color remains dissolved in the water; since water is more dense than diethyl ether, the water will be on the bottom.

Compare with the separated mixture of water, food color, and methylene chloride in the separatory funnel on the right.

Determining densities: D=M/V so you could measure the mass of a measured volume (weigh volumetric glassware, measure volume into glassware, weigh glassware with solvent) and divide to determine density.

Adapted From:

http://orgchem.colorado.edu/hndbksupport/ext/ext.html on March 22, 2011

Define the following words in your lab notebook. Use the glossary in Chemistry theory text or a resource such as the McGraw-Hill Dictionary of Chemistry.

immiscible extraction

Week 5: 6.5 Chromatography: Two-Phase Separation of Mixtures

ChromatographyChromatography is another method for separating mixtures. The word chromatography means colorwriting. The name was chosen around 1900 when the method was first used to separate colored components from plant leaves. Chromatography in its various forms is perhaps the most important known method for the chemical analysis of mixtures. Paper and thin-layer chromatography are simple techniques that can be used to separate mixtures into the individual components. The methods are very similar in operation and principle. They differ primarily in the medium used.

Paper chromatography uses ordinary filter paper as the medium upon which the mixture to be separated is applied. Thin-layer chromatography (TLC) uses a thin coating of aluminum oxide or silica gel on a glass microscope slide or plastic sheet to which the mixture is applied. A single drop of the unknown mixture to be separated is applied about half an inch from the end of a strip of filter paper or TLC slide. The filter paper or TLC slide is then placed in a shallow layer of solvent in a jar or beaker. Since the filter paper and the TLC slide coating are permeable to liquids, the solvent begins rising up the paper by capillary action. As the solvent rises to the level of the mixture spot, various effects can occur, depending on the constituents of the spot. Those components of the spot that are completely soluble in the solvent will be swept along with the solvent front as it continues to rise. Those components that are not at all soluble will be left behind at the original location of the spot. Most components of the mixture will move up the paper or slide at an intermediate speed somewhat less than the solvent front speed. In this way, the original mixture spot is spread out into a series of spots or bands, with each spot representing one single component of the mixture, as seen in the illustration of a paper chromatography strip to the right.

The separation of a mixture by chromatography is not only a function of the solubility in the solvent used.The filter paper or TLC coating consists of molecules that may interact with the molecules of mixture as they are carried up the medium. The primary interaction between the mixture components and the medium is due to the polarity of the components and that of the medium. Each component of the mixture is likely to interact with the medium to a different extent, thus slowing the components of the mixture differentially depending on the level of interaction.

In chromatography analysis, there is a mathematical function called the retention factor. The retention factor, Rf, is defined as:

Rf is the ratio of the distance a substance moves up the stationary phase to the distance the solvent have moved. The retention factor depends on what solvent is used and on the specific composition of the filter paper or slide coating used. The Rf value is characteristic of a substance when the same solvent and the same type of stationary phase is used. Therefore, a set of known substances can be analyzed at the same time under the same conditions.In the case shown below, the Rf for the green spot is

Paper chromatography and TLC are only two examples of many different chromatographic methods. Mixtures of gases are commonly separated by gas chromatography. In this method, a mixture of liquids are vaporized and passed through a long tube of solid absorbent material. A carrier gas, usually helium, is used to carry the mixture of gases through the tube. As with paper chromatography, the components of the mixture will have different solubilities and different attractions for the solid absorbent. Separation of the components occurs as the mixture moves through the tube. The individual components exit the tube one by one and can be collected.Another form of chromatography is column chromatography. In this form, a vertical column is filled with solid absorbent, the mixture is poured in at the top, and a carrier solvent is added. As the mixture flows down the column, the components are separated, again, by differing solubilities in the carrier solvent and different absorbencies to the solid packing. As the liquid drips out the bottom of the column, components of the solution will exit at different times and can be collected.

This video presents thin layer chromatography with fluorescent materials, and column chromatography with UV active materials. There is no narration on the video so it would be advantageous to watch with a chemistry teacher (6f): http://www.youtube.com/watch?v=gzp2S0e9o8s

(From CK12 Chemistry 2nd Edition pp 409-412)

Weeks 1-5 Summary Mixtures of solids may be separated by differing solubilities of the solids in a single solvent. Components of a solution composed of a non-volatile solid solute and a liquid solvent can be

separated by distillation. Mixtures of liquids with reasonably different boiling points can also be separated by distillation. Solid compounds may be separated from impurities – purified – by recrystallization. Compounds may be separated based on their relative solubilities in two different immiscible

liquids, usually water and an organic solvent, by solvent extraction. Solutions with several components can be separated by paper or thin-layer chromatography. Gas chromatography and column chromatography are also used to separate the components of

a solution(Adapted from CK12 Chemistry 2nd Edition pp 409-412)

Week 6: Solutions of Solid Chemicals

7.1 Make Up a Molar Solution of a Solid Chemical

7.2 Make Up a Molal Solution of a Solid Chemical

Week 7: Solution of Liquid Chemicals and Mass-to-Volume Percentage

7.3 Make Up a Molar Solution of a Liquid Chemical

7.4 Make Up a Mass-to-Volume Percentage Solution

Week 8: Colligative Properties of Solutions

8.1 Determine Molar Mass by Boiling Point Elevation

8.2 Determine Molar Mass by Freezing Point Depression

8.3 Observe the Effects of Osmotic Pressure

Week 9: 9.2 Observe a Decomposition Reaction

9.1 is skipped as impractical due to smell and toxicity

Week 10: 9.3 Observe a Single-Displacement Reaction

Week 11: 9.4 Stoichiometry of a Double Displacement Reaction

Week 12: 10.1 Reduction of Copper Ore to Copper Metal

Week 13: 10.2 Observe the Oxidation States of Manganese

Week 14: 11.1 Determine the Effects of Concentration on pH

Week 15: 11.2: Determine the pH of Aqueous Salt Solutions

Week 16: 11.3 Observe the Characteristics of a Buffer Solution

Week 17: 11.4 Standardize Hydrochloric Acid Solution by Titration

Introduction to Lab Weeks 18-19: Chemical KineticsAlthough you may not have covered chemical kinetics in the lecture portion of course yet, this will not present a problem for the next group of labs as these experiments are more qualitative in nature and will not involve detailed mathematical determination of reaction rates as taught in most chemistry textbooks. By this point, students will not have difficulty understanding the main point, which is that temperature, surface area, and concentration all effect the speed of reactions.

Week 18: Determine Effects of Temperature and Surface Area on Reaction Rate

12.1 Determine the Effects of Temperature on Reaction Rate

12.2 Determine the Effects of Surface Area on Reaction Rate

Week 19: 12.3 Determine the Effects of Concentration on Reaction Rate

Week 20: 13.1 Observe Le Chatelier's Principle in Action

Week 21: 13.2 Quantify the Common Ion Effect

Week 22: 14.1 Observe the Volume-Pressure Relationship of Gasses (Boyle's Law)

Week 23: 14.2 Observe the Volume-Temperature Relationship of Gasses (Charles's Law)

Week 24: 14.3 Observe the Pressure -Temperature Relationship of Gases (Gay-Lussac's Law)

Week 25: 14.4 Use the Ideal Gas Law to Determine the Percentage of Acetic Acid in Vinegar

Week 26: 15.1 Determine Heat of Solution

Week 27: 15.2 Determine the Specific Heat of Ice

Week 28: 15.3 Determine the Specific Heat of a Metal

Week 29: 16.1 Produce Hydrogen and Oxygen by Electrolysis of Water

Week 30: 18.1 Observe Some Properties of Colloids and Suspensions

Week 31: 18.2 Produce Firefighting Foam

Week 32: 18.3 Prepare a Gelled Sol

Week 33: Discriminate Metal Ions

19.1 Using Flame Tests to Discriminate Metal Ions

19.2 Using Borax Bead Tests to Discriminate Metal Ions

Week 34: 20.1 Quantitative Analysis of Vitamin C by Acid-Base Titration

Week 35: 20.2 Quantitative Analysis of Chlorine Bleach by Redox Titration

Week 36: 21.1 Synthesize Methyl Salicylate from Aspirin