Science Experiments - Feedback from our Visitors

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From Philip-
I've used a chunk of dry ice about the size of a six sided die to carbonize a 1 liter bottle of water. A concern I might raise is that the dry ice should be food grade if consumption of the desired liquid is anticipated. You can use fruit juice or some flavored drink mix to make your own soft drinks. This also works for carbonating wine to get a sparkling drink....
I like your site... great things for kids to do. a few others:

From Steve

Please mention in your "Home Lab" page, under "Electricity", to have the
power strip mounted above the table top so spilled liquids do not
splash or run into the outlets openings. A "Ground Fault" receptacle
will prevent an accidental electrocution at any rate. These are some
"should haves" that are discussed "after the fact".
Thank you for your attention, and maintaining these wonderful pages
furthering our interest in science.

...and if that's not the truth, may I be struck by

lightning from the Heavens abo#%!>]>%}&[{]]]]]]]]




I just found your animation page, and I think it's great. There's one animation trick I used to do as a kid that I think you'll like. It's essentially a 2-page flipbook made from a single piece of paper folded in half like a greeting card. The cover of the "card" and the place where the message would be each have one of two similar pictures. Something that shows a simple repetitive motion is best (my favorite is a woodpecker poised to peck a tree, and in contact with the tree).  Roll the cover around a pencil so that it's curled enough to see the inside picture. Use the pencil to quickly roll and unroll the cover. I would sketch the cover picture, then draw over it hard enough to make an impression on the inside, and use that impression as a guide for the inside picture. I think it's a neat trick for those without the time or patience to make a whole flipbook.

Thanks again for a great site.



When my daughter was in fifth grade she did a science experiement with three jars of water and three eggs. One jar was only water and the egg sank. One jar was only salt water and the egg floated to the top. The third jar was half water and we siphoned in salt water with a straw, therby, making the third egg float in the middle of the waters. She won third prize at her science fair and would have gotten first if we had been on time. She is now a mother herself. We can hardly wait to let her kids do such an experiment, even if it only at home.
Dear Brian,
I am in sixth grade and we are having a science fair. I would like to do an experiment with dry ice that I saw on tv. The man blew bubbles over an aquarium filled with dry ice and fog and the bubbles didn't sink. they hung in the fog for a very long time.
I have tried this at home and it works the same. I timed how long it took bubbles to drop to the table without dry ice, over regular ice cubes and over dry ice. I have all my data and information, but....
I'm not sure how to explain what happened. Why do the bubbles hang in the fog? Is it because the CO2 is denser?
If you could explain this to me it would help me with the question section of the science fair.
Thanks for your info. I hope you can help
Hey Brian I got a blue ribbion! I got the three best scores I could get. Thanks alot for your help, I really needed it.
I`m a 6 grader in Huntsville AL. Every six weeks our teacher makes us do a science experment. there are 90 people in the sixth grade and after a while it`s hard to find a good science experment. Your science experments helped alot. THANKS!
P.S. E-mail me some time.
Read your web page on making fog. Here's a good one for you. You can buy propylene glycol as "animal-safe automobile antifreeze" or as "RV-water system non-toxic antifreeze", or the way I get it, as the reagent chemical from a veterinary supply (ketosis treatment for dairy cattle). One gallon for something like six bucks. Cheapest way to get "food/medical grade".
Mix one ounce distilled water with one ounce of propylene glycol. Heat an old metal pan up until it is about 400 degrees F. Toss the two ounces into the hot pan. The room will quickly fill with dense white fog, that is relatively non toxic, and non-staining (fog juice sold for the commercial fog units is polyethylene glycol, it slimes everything and never evaporates while proylene glycol quickly eliminates itself). The refraction index for propylene glycol is very good, and I find it is an excellent fog to use with lasers for "beam effects". :)
There is a very beautiful crystal like growth I discovered while attempting another process that is very easy to produce. They are pale whitish green in color and have very fragile tendril like protrusions. I have no Idea what the exact proportions are right now, I have them written down somewhere...
  1. To a small amount of muriatic acid, slowly add aluminum until no reaction can be seen to take place.
  2. add common bleach to the mixture. It should form a dense gel like consistency.
  3. allow this to set for a day, then using an eyedropper transfer a small portion of the gel like substance to a piece of paper and let it set for a day.
  4. when you come back there will be a very beautiful structure. I am not too sure that it is actually a crystaline formation, but they are beautiful nevertheless. One drawback from this procedure is the potentially dangerous fumes created in the process.

you should try making a simple laser show machine with rotating mirrors...
  1. Attach a small circular mirror (diameter = ca. 3 cm in diamter) to a small electric engine.
  2. When you shine the laser on the mirror you get a reflected laser circle.
  3. Direct this mirror towards a second mirror-engine (with a slightly larger mirror) and you will get a quite complex and cool reflection pattern.
  4. If you add even a third mirror-engine you should be able to create very complex figures and shapes with your engines.
  5. For good results, add regulatable resistor to each power source such that you can regulate the speed of each mirror. Now you can combine different "mirror frequencies" with each other and get totally different patterns.
Try it... its really cool for parties etc.!
Trondheim Young Scientists (Norway)
Q: I am an elementary education student in my professional semester. Currently I am doing a thematic unit geared towards first graders on camping. If anyone has any great ideas that have worked in the past for science and camping I would greatly appreciate the help.
A: Hi Sheri,
There are lots of opportunities to learn some scientific concepts on a camping trip (if that was your question). Some that come to mind are: and many more you could spend hours brainstorming.
Thank you for the help. You gave me some great ideas to go on for my camping unit.
Q: I'm conducting a search for my son's 7th-grade science teacher.
He would like the formula for making glow-in-the-dark paint pigment and/or the formula similar to that used in the Cyalume (tm) light sticks.
If you know where I can get these, please respond directly to me via EMail.
A: Hi Frank,
The glow-in-the-dark pigment is called phosphorescent Zinc Sulfide. I will be posting some experiments using this substance soon. I will also be describing how to make slime (the formula for which is on my site) glow in the dark, and react to magnetic fields. I'm working on these right now; give me a little time to finish.
Q: I am interested in experiments you can do with over the counter medicines or cosmetics. Do you have any idea how to find a site with this info?
How can we test the effectiveness of allergy medicines?
How could we test the anti-inflammatory qualities of aspirin vs naprosyn?
How to test cough medicines?
We homeschool and want to do some of these experiments. Any guidance?

A: Not really. I don't think it would be too easy to do the kinds of clinical trials that the drug companies do. Personally, I would stay away from these types of experiments.
We're trying to find out how to build a simple motor dc. any suggestions?
Great website.
I am retired and helping teach science in my wife's third grade class and assiting in the 4th and 5th. I love the stuff and am always looking for some way to make education more connected to the real world. Thanks for putting together all this information.
Well, thanks for your comments, Tim! I think it's great you are helping out. And, yes, making education more connected to the world outside of school is an important thing to do. Best of luck to you and your wife.
Q: I was wondering if you could help. On a recent episode of The Lateshow with David Letterman a girl did an experiment where she mixed hydrogen peroxide with a pink coloured liquid. The result was a bright yellow/green liquid that glowed in the dark.
I was wondering if you knew the other chemical(s) involved besides hydrogen peroxide that was used - or if you know of anything that will produce a similar effect.
A: Yes, that is the "Luminol" reaction. I have been planning for some time to post that one, because I like it very much. You might be able to find it on the net by searching for Luminol.
Q: Hi I recently visited your webpage, and I didn't find any science experiments involving the growing of crystals. If you know such a procedure, or if you know where to find it, I would greatly appreciate it if you would let me know. Thanks very much! Cordially,
A: I will have procedures soon. Right now I am growing Rochelle Salt crystals. There is a good book at your library about this. It is called "Crystals and Crystal Growing". I have a review of the book on my website (see "Book Reviews" section). If it isn't at your library, you can buy it from Amazon by linking there from my book review.
Q: Hi! Love your site. I have a comment and question. Is it possible to find out about the experiments that are "talked" about in feedback. Some sound very interesting but I would need more details, are they written up anywhere?

I have read that you can purchase sodium carbonate and phenol red from a Spa store. Are these o.k. to use for a "kitchen" chemist and is there a list somewhere of chemicals that can be found at places other than a science company and that aren't on your chemical list?
Thanks for your time.
A: Are you referring to Phillip's e-mail, in which he has a list of fun things to try? Let me know, and I will try to direct you to more information.
Yes, sodium carbonate is safe no matter what the source. And phenol red is an indicator that is also safe. The first is for lowering the pH of a spa or pool,; the second is, I believe, for measuring the pH. Creating a list of commonly-avaiable chemicals is a great idea. I will investigate.
Q: hello just looking through some of your stuff and i wanted to say that all your stuff is a 10 year old girl and alot of my friends think im crazy for liking science so much but as long as i like it ill keep on.
Please write back to PaMich.
A: Hi PaMich, I have a ten-year-old daughter myself.
I'm glad you liked the stuff.
I hope you will do some of the experiments.
If you do, please let me know how you liked them.
Thank you very much for writing.
Oh I have. I can't remember whitch ones but I have done a lot. They haven't all worked but it's still fun and teaches me more about science. I'm always looking for a new one. My name is Michelle.
A little advice keep doing all those good experiments.
write back soon
Hi Brian,
Just found your site...very impressive...I will definitely make use of it. Please notify me of any updates.
Q: Hello, my name is Brandon and I am a cadet at the United States Air Force Academy. As part of a senior design class, I am part of a class that has been tasked with building focused sound dishes for a children's museum here in the Colorado Springs area. Right now, we are looking at ideas for how to go about in constructing these dishes. We are trying to decide materials, dimensions, etc. The two dishes will be 40-50 ft apart. We are also looking to see if there are any mathematical formulas for designing these. Any advice, help, information, or resources that you could provide would be greatly appreciated.
Thank you.
Hi Brandon,
The reflectors you build will look a lot like large satellite dishes. In fact, used satellite dishes may be the way to go. Be sure that they are the solid type, not the wire ones.
The form of the curve is a paraboloid of rotation. This form starts with a parabola, which is a two-ddimensional curve, then rotates it to get the third dimension.
A parabola has the equation
To plot the curve, first decide what "f" (the focal length) is going to be. I suggest 3 or 4 feet (36 to 48 in.). then plot "Y" values for each "X" value starting at zero, and continuing to the edge of the dish, about 50 inches. This will give you half of the parabola.
Now you need a manufacturing technique. You could make a parabola-shaped template and layup a dish over it. If you have someone skilled in boatmaking, you could make a mold and build the dishes out of fiberglass. If not, maybe you can use other materials. Maybe you can fashion a dish from plastic sheets - thick ones, not "trash bag" material. Cut the sheets into pie sections and tape or weld them together.
Q: OK, I'm doing a project in biology, and they said to research it some so any info you can give will help. The question is "Does smell affect taste?"
A: Blindfold someone. Then feed them a piece of apple while having them smell an onion. Report what they describe.
Very nice site Brian! I'm an elementary education major and found some great info here. Thanks
Q: Hello, My name is Michael Brassil writing on behalf of the Josie True internship. We are a non-profit group of multimedia students at the University at Buffalo. We are currently creating a CD-ROM for girls ages 8 - 11 emphasizing math, science and technology.
Please visit our webpage at Josie True.
We are trying to incorporate some off-line scientific experiments on our website. We already have several online activities, but none are very heavy on content. I was hoping we could incorporate some of the experiments from your website: Brian's Science Website.
These exercises would be strictly preserved as offline content, not associated with the cd development, and full credit would of course be given. Thanks in advance for your cooperation.
Feel free to contact me or the project producer.
A: I replied to this message before, saying, "sure, go ahead", or something like that.
Today I had the chance to visit your site for a bit, and I would like to say that I think it's great! I have three daughters myself, and I am going to show it to my oldest (age 10) as soon as possible. Great job!!!!
Q: My daughter-in-law is a second-grade teacher and has asked me to perform some simple science experiments for her class. Can you give me any hints ? I have printed out your Experiments with Dry Ice from The Saturday Scientists and will try some of these.
Thank you,
A: I enjoy doing the Animation stuff with the kids. I also enjoy the mini- maglite experiments, but you need to be able to darken the room, and work in small groups. The kids ALWAYS LOVE the dry ice experiments (the popping film-cans, especially!). They also quite enjoy making slime.
Q: Do you supply a kit, or the chemicals, to perform the iodine clock reaction, and, if not, can you suggest a supplier of either a kit or the requisite chemicals. Thank you.
A: I have recently stopped all sales activity on this website, so that I too may enjoy my science hobby.
Try searching for the individual chemicals on ebay or a mainstream science supplier like Tri-Ess sciences in Burbank CA.
Q: I was wondering where I could find science experiments dealing with mixtures and compounds, or with atoms. Thank you for listening to me and please write back.
A: The difference between mixtures and compounds is that mixtures can be separated again by physical means. Compounds must be separated by chemical means.
This is an indication that the atoms in a mixture are not holding onto each other, they just happen to be nearby. In a compound, the atoms of the constituent substances are connected atom-to-atom by chemical bonds. Chemical bonds are where the atoms either share electrons between them (valence bonds), or exchange electrons, and are then attracted to each other by electrostatic forces (ionic bonds). You can mix sugar and sand together and then separate again by dissolving out the sugar in water. You can mix iron powder and sulfur together, and separate it out again by using a magnet. But if you heat the mixture, the sulfur and iron combine (rapidly -watch out!) to form a compound, Iron sulfide.

Q: Hi Brian,
I'm a 51 year old kid that has always had a fascination for these optical devices and the history behind them. Might you know where original or replicas of these items might be purchased from? Thanks a lot,
Have you seen this site?
Van Cort Instruments
Here's another one:
Deutsche Optik

Q: I did the dry ice/35mm film can demonstration for my daughter-in-law's second-grade class and they loved it !!! Do you have any suggestions for other experiments for this age group ? Thanks
Q: Hi,
Years ago, probably 60 years ago!, I would get a monthly packet called Things of Science that was undoubtedly a gift subscription from a relative. These packets, small cardboard boxes that came in the mail, were geared toward pre teens. They contained an explanation of that month's topic, eg. magnetism, and had the material etc with instructions to perform or build an experiment or working device. I know those things influenced my subsequent technical career; I can still picture some of those kits and the subjects. Does anything like Things of Science exist today?
Your website looks interesting - I haven't explored your links yet but will now. Thanks,
A: Hi, Ben, Yes, I remember Things of Science too. It was pretty terrific.
It was run by a nonprofit organization called Science Service. See A brief look at their website revealed that they mention Things of Science, but didn't indicate that they are available.
Science Service was founded in 1921.
Q: I've been looking for one of "those things" that you picture on the heading of your home page where light spins the white/black tabs in a vacuum ball. Do you sell them? Any ideas where to get them?
Tom Gaston
Q: I`ve been reading all the posts for some time now so I thought it was time I posted in. Now this may be an old chestnut but I need to know how my radiometer works.
On the bottom is a sticker which says it is powered by the sun, I take it that this actualy means IR radiation. So why does it spin? I thought it might be the excitation of air molecules next to the black surfaces but I`m not real sure.
Q: Yes, it is powered by the kick that air molecules are given by the black surface. The black surface absorbs more radiation, so is warmer than the white or silver surface. You can also power your radiometer with hot water. Try it! Put the radiometer under the tap, and run the hot water over it. Then, when it's going really fast, switch over to cold water. The vanes will stop, and start going the other way!
Q: Hi there,
I stumbled upon your site thanks to a search using my Mac's handy Sherlock. We have a chunk of dry ice and were looking for experiments, and your page of experiments should keep us busy all morning. And since we are a new homeschooling family, I'm definitely bookmarking your site for further science projects and answers to questions.
Glad to have found you!
A: Hi Jennifer,
We are a homeschooling family too. Glad you found us.
Q: Hi Mr. Rich,
My name is Salwa and I'm a technical instructor at the IDX Institute of Technology in Burlington, VT. My group is working on a project called "Learn to Earn" with highschool kids where we go into a school and have an hour in every class to get kids motivated about science. Currently enrollment in science programs in Vermont colleges are very low, and alot of the technical expertise in the state ends up coming from outside. This is a chance to bring more Vermont kids into a science related field.
I saw your very interesting website and I'm not sure if you're still working on this. However, if you are, I wanted to see if you have any ideas for an exercise that I can do with the kids to give them a flavor of what science is about. Each class has about 20-25 students and I have only one hour to talk, answer questions and do an exercise. So basically what I need is something that they can do in about half an hour. Any ideas will be highly appreciated. Thank you in advance and good luck on your work.
With best regards
A: Hi Salwa,
Yes, my site is alive and well. I don't get as much time as I would like to add to it; I have a large backlog of experiments to write up for the site. I would like to ask you to help me prioritize. Look at the following list of experiments that I have done in an outreach situation similar to yours. If you like the sound of any of these, I will send you details on how to perform them. The link is:
Science Outreach.
Good luck, and let me know if you are interested in more info. Best regards,
Dear Brian,
Thanks so much for writing back so quickly. The following sound like things I'd like to do:
....I'll stop at these three. They all sound interesting. But for the short time frame, something that will need some moving around be fun as well would be ideal. I hope it's not too much of a problem to give me the details on the exercises! Thanks again,



Everything you use in the construction of your zeppelin must be as lightweight as possible. Helium has a lifting power of only 1.06 grams per liter (helium is 1.06 g/l less dense than air at sea level). For the gondola frame, I use plastic Flexi-Straws. These are the ones with the accordion bend near one end that enables you to bend the straw without it collapsing.
  1. Build a rectangle using four straws. Two of the straws are first shortened by cutting the "long" end to place the accordion section in the center of the straw. Then assemble the rectangle by using the straws in alternating order: long, short, long, short. To connect the straws to one another, pinch one end and insert into the other.
  2. Now that you have a frame for your gondola, you need to construct a gondola body, which serves as a place to mount the electric motor and batteries. I use light card stock from a manila file folder. The bottom fold of the folder, and the scored line next to it are separated by just the right distance to form a nest for the electric motor. Fold the score and arrange the folds so that the flat trough formed is perpendicular to the sides of the folder. Cut the excess top portion of the file folder away as in the diagram.
  3. Attach the gondola body to its frame with transparent tape. Use the tape sparingly; you want strength but not extra weight.
  4. Set the motor into the trough of the gondola body. Secure with tape.
  5. Arrange the button cell in the trough and secure one of the two leads to the cell. You may have to reverse the leads later, so don't go crazy making it secure yet.
  6. [Make a propeller]
  7. For the balloon part I use a large dry-cleaning bag. These seem to have the thinnest walls of any bag. You may want to keep an eye out for large trash can bags that also seem to be very thin. The real "cheapie" kind will be the lightest. A dry-cleaning bag unfortunately has a hole at the closed end. This hole is where the hook of a clothes hanger passes through the bag. You will have to close this hole. I have used tape. Or you can tie the bag closed with kite string. If you tie the bag closed, you will want to trim off the excess "dead weight" of the part of bag that protrudes beyond the string. And if you use tape, don't use too much! If you use a light weight trash bag, you won't have this problem.
  8. Squeeze all of the air from the bag.
  9. Fill the bag with helium, and tie it closed with string or fishing line.
  10. Use more string to attach the bag to the gondola. Support the gondola on all four sides.
    Brian, The site you have put together is great!!
    I'm an educational consultant currently doing work with the Space Science Lab at Berkeley in conjunction with the NASA Space Programs. I assist in the development of the educational components for their educational outreach program and spend much of my time searching sites for applicable, practical educational materials. Your site has these qualities. Thanks for the refreshing change. The educational outreach programs I have been working with are two consortiums, SEGway and SECEF. These consortiums do have some cheap astronomy stuff you may want to add. The NASA and NASA supported web sites have tons of science materials, some of it on line and some of it materials to order. Most of it is free and what isn't is at cost. SEGway and SECEF web sites have astronomy lessons, information, activities, labs, etc. Check the web sites and see if you think this is something that would fit as one of your links. Good luck, have fun and kudos,
    Susan Highlund

    Q: Hello Brian,
    Do you offer a kit for an oscillating clock demo? I have received a kit from Flinn Scientific, Inc. in the past. I would like to use a closer supplier. Your web site has great ideas.
    A: Do you mean clock reaction experiments? I don't have a kit now, but it is one I have wanted to put together for a long while. I just might do that, now that someone has asked me.
    Just dropping you a note that we "stopped by" looking for info we could use for a second grader to do a science fair experiment using electricity. Enjoyed the site. May come again to do some of the experiments you have listed.
    the Mandelko Family
    Q: I have a question. The discussion is natural gas. Does natural gas get shipped to homes or businesses in a gas form or a liquid form?

    A: Natural gas is shipped to homes and businesses in a compressed, gaseous state.
    Q: Second Question - I am saying, "If you raise the pressure high enough you can turn anything from a gas form to a liquid form". Is this a correct statement?
    A: No!
    It depends on the substance. There is a critical temperature for a gas, above which you can't make it condense no matter how much you increase the pressure. For example, Carbon Dioxide has a critical temperature of 31oC. Just below this temperature you can liquefy the gas by compressing it to about 1,070 psi. Above this temperature you can't liquefy it at all.
    COPYRIGHT © 2000-2004, Brian Wesley Rich
    Updated 26 April 2004