Your Safer Source for Science

Since 1977

Address P.O. Box 219 Batavia, IL 60510
Phone 800-452-1261
Fax 866-452-1436

Chemistry FAQ

Chemistry FAQ

You've been storing chemicals on the school premises which have not been used for decades. Suddenly the school decides those chemicals you no longer use have to go. Probably a good decision, but the actual removal should be done with much planning and consideration. The problem has been there for a long time. Will another few weeks matter while you examine your options? Hurried solutions to problems are almost always expensive and often poorly done. Time should be allowed to examine all of your disposal options. There may be more options than first appear. What are your options for chemical disposal?

Option A - Contact your state department of education. Many states have a state science supervisor who may be able to make suggestions or advise you about existing programs already operating.

Option B - If your school is located in an area near a college or university, that institution's chemistry department may be able to advise you about the disposal methods they employ. You will want to prepare a complete list of the substances you consider excess. There is a chance the college may be able to use some of these materials.

Option C - Have you shared your list of excess materials with other schools in your system or other neighboring schools? Assuming some of the chemicals involved are still useful, perhaps another school can use what you consider excess.

Option D - Contact your state equivalent of the federal Environmental Protection Agency (EPA). Most states have a state EPA. Discuss the problem with this agency. Perhaps they have valuable suggestions.

Option E - Try to contact an officer of your state's science teacher's professional association. Most states have organized science teacher's groups. Other teachers have faced problems similar to yours. Bring their experience to bear on solving your problem.

Option F - In many metropolitan areas, there are local sections of the American Chemical Society (ACS). Any area with a lot of chemical industry is likely to have a local ACS section. Contact these professionals. They may have some helpful insights.

Option G - Pay a commercial firm to assist in removing these materials. This is a very, very expensive option. Be sure you ask for references from such a commercial firm. There are reputable and reliable firms operating all over the U.S.A. Just be careful in making your choice.

Option H - Is there a company in your town that also disposes of laboratory chemicals on a regular basis? If so, could you possibly piggyback your excess chemicals with his and split the cost? This is an option many teachers have found very useful.

Option I - Do the disposal work yourself. If you elect this option, you will want to examine the disposal methods provided in the Flinn Scientific Catalog/Reference Manual.

Do not act in haste. If you will take some time to properly package many of the hazards on your shelf, that will allow time to examine your options.

If you have elected to use the disposal methods published here, there are some further considerations that need your attention. Those considerations are:

1. Have you checked with regulatory officials in your area regarding these procedures? Do not-we repeat-do not use these procedures if local regulatory officials have not approved.

2. You will need to make a list of the safety aids needed for these procedures: e.g., fume hood, apron, chemical splash goggles, fire extinguisher, gloves, etc.

3. Never work alone! Find a competent assistant and proceed to work as a team.

4. If a particular method is confusing or you are not familiar with the chemistry involved, do not proceed. Call us; we will be glad to help: 1-800-452-1261.

5. Do some practical cost analysis. In many cases, the procedures require the use of large quantities of neutralizing chemicals and other expensive materials. You may find that your cost analysis may cause you to go back and examine disposal option G, i.e., pay a commercial firm to remove the chemicals.

6. Always practice your intended disposal activity on a tiny (micro) sample of the targeted substance before moving on to handle the larger (macro) volume. A reaction that liberates enormous amounts of heat may require that your reaction vessel be immersed in an ice bath to better control the reaction temperature. You will only make these discoveries if you "practice" with a very small sample before proceeding.

7. All of these procedures are best done in a very well ventilated laboratory and preferably in a good, efficient fume hood. If you elect to perform a procedure out of doors, then stay upwind of the reaction and be sure your activities do not disturb or threaten your school's neighbors. 

8. Make a checklist of all items needed for a particular method before you start the procedure. Have all materials at hand and immediately available.

Summary - Chemical removal and disposal are serious undertakings. Examine your options carefully and responsibly. Read the information provided in your copy of the Flinn Scientific Catalog/Reference Manual for specific solutions to the problems you encounter regarding the disposal of laboratory chemicals. No other science supplier provides such information and solutions. Flinn Scientific is your problem-solving source.

Lecture bottles cannot be reused, refilled, or recycled. Your best bet is to make sure the cylinder is completely empty and discard the cylinder in the trash. For your next purchase consider refillable lecture bottles. They can be refilled as often as you like and will save you money.

Yes, as an alkali metal, potassium is an explosion risk. It will react violently with water.

Peroxides have been known to develop on the exterior surface of potassium metal. These peroxides have been known to react explosively with the light oil (kerosene) in which the product is stored when the science instructor cuts the product into small pieces. Be sure you provide personal protection when dealing with this very reactive metal. If you have a choice as to which alkali metal you elect to buy and use, sodium metal might be your better choice since, upon aging, it does not develop peroxides.

A science teacher's best option is to purchase potassium already pre-cut. Flinn Scientific offers a bottle of five small pieces for demonstration purposes. ( Catalog # P0204)

Sodium metal is best stored in a glass container covered in dry mineral oil. The bottle should be labeled appropriately. The bottle should then be placed in a heavy-duty plastic bag and sealed with a twist-tie. Should the container be broken, the sodium metal will still be contained in the plastic bag. The container and bag should be placed into a metal paint can, surrounded by kitty litter and sealed. The outside of the metal can should also be labeled appropriately.

There are basically two options:

  • Portable lab burners
  • Hot plates

Flinn Scientific offers two types of portable lab burners-butane and propane burners. The butane burner produces a flame about the same temperature as a standard Bunsen burner. The propane burner produces a much more intense heat than the butane burner.

Hot plates are the safest method for heating in the lab. They do not present an open source of flame. Temperature settings are adjustable and can reach 538 °C (1000 °F). The heating elements are embedded in the heating pad so no exposed or glowing heating elements are present.

Several laboratory chemicals that Flinn Scientific sells have melting points around room temperature and may be liquid or solid depending on the temperature in your storeroom. t-Butyl alcohol has a melting point of 25 °C which means it will be a solid in most laboratories. Remember, melting point is a sign of purity and the higher the melting point, the purer the material. Flinn t-Butyl alcohol is very pure and will have a melting point very close to 25 °C. To melt the product, loosen the cap and place it in a container of hot tap water. Be careful so the bottle of chemical does not tip over.

If your acid is brown, first determine if the bottle or the acid has discolored by pouring a small amount into a beaker. The common culprit for discolored acid is a small amount of organic material such as paper or oil dissolved in the acid. The acid is still useable as an acid and frequently solutions made from discolored acid are colorless. A slightly discolored bottle may be due to the discoloring of the PVC coating which does not affect its performance.

Yes. You must rinse them clean with 70% isopropyl alcohol and then again with water. Store them in a bag or box to dry.

You can't make sodium silicate solution from the solid in the laboratory. Extreme pressure and heat are required. Please purchase the pre-made solution.

A 1 molar solution is made by dissolving 1 mole of the chemical in approximately 800 mL of distilled or deionized water. This is done in a 1-liter volumetric flask. When the solid has dissolved, the flask is filled to the 1 liter mark and stirred.

Flinn Scientific has published recipes on how to make over 100 solutions for the high school science laboratory. Please consult the Flinn Scientific Catalog/Reference Manual for more information.

Slime! The word itself conjures up images of learning opportunities oozing with fun. Whether you use slime to motivate the creative writing talents of middle school students or to initiate a discussion of polymer chemistry with advanced secondary chemistry students, slime brings excitement to learning. Bring a smile to your students' faces...Slime them!

Click on the files below of ChemFax! instructions for making Guar Gum Slime and Polyvinyl Alcohol Slime. Read each ChemFax! and choose the slime that is appropriate for your lesson plan and your students.

Guar Gum Slime
If you want free-flowing, "goopy" slime, similar to the slime often seen in the movies (Do you remember slime-covered Bill Murray in Ghost Busters?), try Guar Gum Slime.

Polyvinyl Alcohol Slime
Polyvinyl Alcohol (PVA) Slime is less free-flowing than guar gum slime. PVA is an ingredient in many adhesives. PVA is the world's largest volume, synthetic, water-soluble polymer.

Flinn Scientific offers the educational fun of slime in convenient Chemical Demonstration Kits. These affordable kits include helpful "Teacher Demonstration Notes" and enough materials to do each demo seven times. Slime ingredients can also be ordered separately. See "Slime Preparation Chemicals" in the Chemistry of Toys section of your Flinn Science Catalog/Reference Manual.

Fluorescent Slime Demonstration Kit (AP9108) 

Slime Demonstration Kit (AP1829)

Slime for Everyone!-Student Laboratory Kit (AP5393)

A common problem in school laboratories is the separated mercury column in a thermometer. The instrument(s) can be made whole if you rigidly follow the procedures suggested. Other methods may be employed but could cause irreparable damage to these expensive instruments.

Cooling Method: Place a small piece (about 1 in3) of dry ice in a 150-mL Pyrex® beaker. Over the dry ice pour about 75 mL of one of the following organic solvents: acetone, iso-propyl alcohol, ethyl alcohol or methylene chloride. There will be a lot of gas evolution (CO2) as the dry ice evaporates, but soon it will subside as the dry ice (-­78 °C) cools off the organic liquid. This mixture will be very cold so don't put your fingers in it.

Hold your separated column thermometer in a vertical position with the bulb portion down. Gradually immerse the bulb only into your cold dry ice/alcohol bath. The mercury column (broken column parts and all) will retreat into the bulb. Continue to immerse the bulb only until all parts of the column are in the bulb. If all the broken column parts will not retreat into the bulb, remove the bulb from the cooling bath, allow the bulb to warm for 3­5 minutes and repeat the process. If the column will still not reunite abandon this method. Do not-we repeat-do not swing the thermometer to create centrifugal force to reunite the broken mercury column. This practice is dangerous, could fill the room with mercury droplets if the thermometer breaks, and should not be done.

Some additional alerts: Do not touch the supercooled bulb until it warms for several moments at room temperature. Do not immerse the very cold bulb in another liquid until it warms. Locate a tray of some kind in which to do this whole procedure so that if a mercury thermometer breaks you have a tray beneath the thermometer to control the spilled mercury. Remember: immerse the bulb only and never immerse the stem or column. Freezing the column will cause the bulb to fracture.

Are the "oohs" and the "aahs" from excitement and amazement missing in your chemistry classroom? Bring back some of the fun and excitement of chemistry by using a Flinn Chemical Demonstration Kit.

We have developed over 30 exciting demonstrations designed specifically for your first year chemistry students. We guarantee you will find each demonstration to be "magical."

Fast and Easy - Chemicals and chemical solutions are already prepared. No preparation is required. All you need to do is open the box, dispense and measure the quantity of chemical required, and conduct the demonstration. We have provided enough of each chemical to perform the demonstration seven times. Once to practice, five times to perform with your students, and once to cover "Murphy's Law."

Guaranteed to Work - Many times demonstration failures are the result of old, poor quality chemicals. We guarantee your success because you will always be using fresh, new chemicals.

Affordable - No longer will you be required to purchase a large quantity of chemicals only to have them on your shelves for decades. We provide you with just the right amount of chemical needed to conduct the demonstration seven times.*

Documented - Each demonstration kit includes our "Teacher Demonstration Notes." We will tell you what the demonstration does, the procedure to be followed, what reactions will occur, and tips on how to "pull off" a demonstration your students will never forget.

Safe - No longer will you have to be concerned with old chemicals, chemical storage problems, or future chemical disposal problems. We provide you with just the right amount of chemical needed to conduct each demonstration.

Excite, energize and bring back the "magic" of chemistry using Flinn Chemical Demonstration Kits.

*No lab apparatus furnished with kits. Lab apparatus required is common material available in most school science departments.

Reagent grade chemicals are selected and best suited for general laboratory experiments. Chemical purity conforms or exceeds quality specifications established by the American Chemical Society.

Laboratory grade chemicals typically meet a minimum purity standard and are usually acceptable for experiments and demonstrations which do not require qualitative results.

Regardless of the chemical's quality, Flinn Scientific inspects each and every chemical it packages for freshness and quality.

Flinn chemicals are the best!

Several common halogenated hydrocarbons have been phased out due to the Montreal Protocol on reducing chlorofluorocarbons that cause harm to the ozone layer. Chloroform, 1,1,1-trichloroethane, and 1,1,2-trichlorotrifluoroethane have been used for years in halogen experiments, denser-than-water demonstration, and extractions and are no longer available. Some substitutes for heavier-than-water, non-polar solvents are trichloroethylene, methylene chloride and perchloroethylene. Mineral oil or hexane work well for the halogen solubility experiment but are less dense than water.

Flinn pH meters should be stored with a few drops of pH 7 buffer or tap water (never use distilled water) in the cap of the meter.

Both FedEx Ground (FedEx) and United Parcel Service (UPS) have instituted a $25.00 per hazardous package shipment charge.

Flinn Minimizes HazMat Fees!
Yes, it's true! Flinn will will help to pay your hazardous materials shipping fees! The rising costs of hazardous materials shipping fees have been a growing concern of many science teachers. The fact that Flinn limits these charges to only $19.75 per order will be a big relief to science teachers and their budgets all across the country.

Flinn knows your science supply budgets are tight and every penny counts. Flinn Scientific is helping you save money so you can spend more of your precious budget money on the science supplies you need...not on hazardous materials shipping fees.

Just Another Reason for you to order your chemicals and science supplies from Flinn Scientific!

Most items in the Flinn Science Catalog/Reference Manual can be shipped air freight. The exceptions to this rule are hazardous chemicals.

If a chemical has a hazard alert listed in the chemical section of our Flinn Science Catalog/Reference Manual it can not be shipped air freight. Kits containing hazardous chemicals also cannot be shipped air freight.

Generally, all orders placed before 12:00 CST can be shipped air freight the same day.