Our Science Center is dedicated to brining new information to children about the world of science. Our goal is to provide links and educational material to children about the world of science. The links on the right will take you to Exploratorium Science Explorer, where you will find alsorts of fun experaments you can try at home. We have also provided videos on various different topics. We hope you enjoy this section and we would love to hear any ideas you may have to make this section better.
BrainPOP.com offers many educational videos on their website that discuse the world of science and technology. Check out their free videos and try their 5 day free trial.
Fun Science Videos
Supersaturation using Sodium Acetate (AKA: heating pad)
Warning: This is not an expariment you should try at home, but an example of Supersaturation implimented in real world turms. In other words, watch and learn, but don't try this at home kids
The chemical that is being used in this video is called Sodium Acetate (NaCH3COO) which is the sodium salt of acetic acid. It is an inexpensive chemical produced in industrial quantities for a wide range of uses.
Sodium Acetate is considered Irritant. For full information refer to the MSDS sheet.
Whats happening
Sodium Acetate has been added to water until the point of Supersaturation. When they are heated to around 100 °C, and subsequently allowed to cool, the aqueous solution becomes supersaturated. This solution is capable of supercooling to room temperature without forming crystals.
When the solution comes in contact with impurities (Dust, finger, metal disc in a heating pad) which causes the solution to crystallize into solid sodium acetate trihydrate again. The bond-forming process of crystallization is exothermic, hence heat is emitted.The latent heat of fusion is about 264–289 kJ/kg. Unlike some other types of heat packs that depend on irreversible chemical reactions, sodium acetate heat packs can be easily recharged by boiling until all crystals are dissolved. Therefore they can be recycled indefinitely.
Other Applications for Sodium Acetate
Sodium Acetate is also used in the textile industry to neutralize sulfuric acid. It is also a pickling agent in chrome tanning, and it helps to retard vulcanization of chloroprene in synthetic rubber production.
Sodium acetate may be added to foods as a seasoning, and to alcoholic beverages to decrease the risk of a hangover.
For more information on Sodium Acetate review the information from Wikipedia.
The electrical resistivity of a metallic conductor decreases gradually as the temperature is lowered. However, in ordinary conductors such as copper and silver, impurities and other defects impose a lower limit. Even near absolute zero a real sample of copper shows a non-zero resistance. The resistance of a superconductor, despite these imperfections, drops abruptly to zero when the material is cooled below its "critical temperature". An electric current flowing in a loop of superconducting wire can persist indefinitely with no power source.
For more information on Superconductivity refer to Wikipedia.
How Does a Van de Graaff Generator Work?
A Van de Graaff generator is an electrostatic machine which uses a moving belt to accumulate very high electrostatically stable voltages on a hollow metal globe. The potential differences achieved in modern Van de Graaff generators can reach 5 megavolts. The Van de Graaff generator can be thought of as a constant-current source connected in parallel with a capacitor and a very large electrical resistance.
For full information on Van de Graaff Generator's refer to Wikipedia.
It's an explosion of color! Some very unusual things happen when you mix a little milk, food coloring, and a drop of liquid soap. Use the experiment to amaze your friends and uncover the scientific secrets of soap.
Materials
Milk (whole or 2%)
Dinner plate
Food coloring (red, yellow, green, blue)
Dish-washing soap (Dawn brand works well)
Cotton swabs
How does it work?
Milk is mostly water but it also contains vitamins, minerals, proteins, and tiny droplets of fat suspended in solution. Fats and proteins are sensitive to changes in the surrounding solution (the milk).
When you add soap, the weak chemical bonds that hold the proteins in solution are altered. It's a free for all! The molecules of protein and fat bend, roll, twist, and contort in all directions. The food color molecules are bumped and shoved everywhere, providing an easy way to observe all the invisible activity. At the same time, soap molecules combine to form a micelle, or cluster of soap molecules. These micelles distribute the fat in the milk.
This rapidly mixing fat and soap causes swirling and churning where a micelle meets a fat droplet. When there are micelles and fat droplets everywhere the motion stops, but not until after you've enjoyed the show!
If you have other suggestions or videos you would like to see added to this section please send us your ideas.
Last Updated on Friday, 08 May 2009 07:08
Science Sites
The Exploratorium is a museum of science, art, and human perception located in San Francisco, California. Online since 1993, the Exploratorium was one of the first science museums to build a site on the World Wide Web. Included in our award-winning site are more than 18 thousand Web pages and many sound and video files, exploring hundreds of different topics. The Science Expariments that we list on Silvergateway all come from the Exploratorium, we strongly suggest that you visit and enjoy there emence website.
This site aims to help you really see insects for the miniature marvels they represent and to understand how intertwined our cultures have become with these alien creatures.
Cells are the building units of your body. Cells are so tiny you can't see them with your eyes and there are so many in your body you can't count them. Cells work together to make you think, move, talk, laugh and be you. This site will explore all the cells that make up your world.
Explore how creatures large and small can adapt and survive in the planet's most extreme environments. Discover how dinosaurs lived, what they ate, and whether they really died out 65 million years ago. See the Museum's smallest employees, the flesh-eating beetles, hard at work on our webcam. Lots of fun resorces on this site for the curious at heart.
Learn all about space, see fantastic photos from space & play games. All done in a very interactive environment. Also head to NASA's 50 Aniversory page to learn about the history of the American space program.
Learn all about the natiral world around us, through games & activities, videos & stories & much more.
A history of world environmental events, earth quakes, hericanes and more.
Interesting science news, research tidbits and science discussion.
On March 13, 2008, the International Space Station passed across the field-of-view of Germany's remote sensing satellite, TerraSAR-X, at a distance of 195 kilometers, or 122 miles, and at a relative speed of 34,540 kilometers per hour, or more than 22,000 mph. In contrast to optical cameras, radar does not 'see' surfaces. Instead, it is much more aware of the edges and corners which bounce back the microwave signal it transmits. Smooth surfaces such as those on the station's solar generators or the radiator panels used to dissipate excess heat, unless directly facing the radar antenna, tend to deflect rather than reflect the radar beam, causing these features to appear on the radar image as dark areas. The radar image of the station therefore looks like a dense collection of bright spots from which the outlines of the space station can be clearly identified. The central element on the station, to which all the modules are docked, has a grid structure that presents a multiplicity of reflecting surfaces to the radar beam, making it readily identifiable. This image has a resolution of about one meter (about 39 inches). In other words, objects can be depicted as discrete units--that is, shown separately--provided that they are at least one meter apart. If they are closer together than that, they tend to merge into a single block on a radar image. Since this image was taken, the station has expanded and is more than 90 percent complete, including a full complement of solar arrays. Image Credit: DLR...
){kind=link}
){kind=link}