All the components of glass can be found in two places: the beach and the laundry room. It's possible to melt pure white-silica beach sand into glass, but only at temperatures of 3,000 to 3,500°F. Washing soda, lime or borax (a traditional laundry aid) added to the sand disrupts the quartz-crystal structure of silica and reduces the required temperature to a more practical, though still dangerous, 2,000°F, which I achieved with a backyard grill and a vacuum cleaner.
The phrase “passing the acid test” gained popularity in the gold-rush years of the 1850s when miners used strong acids to determine whether the metal they had found was real gold or not. If it bubbled and frothed on contact with acid, it wasn’t gold. But even these failures produced something interesting and beautiful.
When pure metals cool, they solidify into intricately interlocked crystals. You can’t see the crystals because they fit together perfectly to form what appears to be a uniform mass with a smooth, solid surface. But acid can reveal the structure inside.
About 230 years ago, molten lead that rained from the sky—historically something to avoid at all costs—became a clever new way to manufacture an important commodity: shotgun ammo.
Precisely round pellets fly straighter, but casting each in its own 1/8-inch mold isn't exactly mass production. In space, making them would be easy. In zero gravity, surface tension pulls any liquid into a sphere, the shape with the least surface area for a given volume.
Two chemicals create a glowing (and poisonous) mixture that’s a window into the weird world of quantum physics
By Theodore GrayPosted 07.24.2008 at 4:51 pm 11 Comments
Before the discovery in the 1920s of quantum mechanics—laws that explain the way the world works on the very small scale of atoms and electrons—the fact that bleach and peroxide glow when mixed would have seemed like just another chemical reaction that gives off light, like fire or fireflies. But it’s actually a glimpse into the impossible.
Explosive glass drops demonstrate why your car windshield is so strong and safe
By Theodore GrayPosted 06.19.2008 at 3:31 pm 6 Comments
Break the tail of a Prince Rupert's glass drop, and the whole thing explodes.
Mike Walker; special thanks to Glass Lake Studio
If you want a scientific display of the dangers of pent-up stress, Prince Rupert's drops are it. After the trauma of being dropped molten-hot into a bucket of cold water, these glass balls, named for a 17th-century amateur scientist, turn into bundles of high tension. They're impervious to even the strongest blows, until you find their hot button: Flick the tail, and they explode.
If you ever see a large industrial metal fire (yes, they happen) on the news, you may be surprised at what the firefighters do to extinguish it: nothing. Several metals, including lithium, sodium and magnesium, can burn easily, and from time to time large amounts catch fire in factories. But even heaps of burning metal need not cause immediate panic. They don't blow up; instead they tend to build up ash that chokes off their oxygen supply, so they slowly burn out.
If a few ounces of quicklime mixed with water can make self-heating soup cans, we figured 500 pounds of it could create a self-heating hot tub
By Theodore GrayPosted 04.17.2008 at 4:07 pm 25 Comments
Self-heating soup sounds like something from the future: Push a button on the can, and three minutes later the contents are piping hot. But it's widely available today, along with self-heating coffee and hot chocolate. In Japan, I even found self-heating sake. Pretty high-tech!
Or not. In fact, these products use a chemical reaction known since at least 4000 B.C.—the mixing of quicklime and water. When you roast limestone at about 1,650°F, it converts to quicklime, a powder used to disinfect corpses in war zones. Mix quicklime with water, and it grabs and binds the water molecules, releasing lots of energy in the form of heat. (The material left over, known as hydrated or slaked lime, is the basis of lime mortar, popular in the Roman empire and still used today.)
Soup is OK, but I decided to use the technology to make a self-heating hot tub.
In large quantities, pure liquid oxygen is powerful enough to launch rockets. But even a tiny bit packs a wallop too
By Theodore GrayPosted 03.17.2008 at 12:54 pm 1 Comment
Oxygen is a good thing. Oxygen is life. But if it were much more than one fifth of our air, we'd be in serious trouble. The other four fifths is nitrogen, an almost completely inert, obstructionist gas whose main effect is to get in the way of the oxygen, especially where flame is involved. For every bit of oxygen a fire consumes, it has to heat up and push away four times as much useless nitrogen. With pure oxygen, that damper is gone, and things that merely smolder in plain air go up like dry tinder. In 1967 three Apollo 1 astronauts died in a raging fire when Velcro lit up in their pure-oxygen pressurized space capsule.
To create beautiful electrical-charge patterns like this, you could use a giant particle accelerator. But shag carpeting will also do just fine. Watch how Lichtenberg figures are made in our amazing video
By Theodore GrayPosted 02.15.2008 at 1:06 pm 19 Comments
There are many unusual things to see around Newton Falls, Ohio—the Wal-Mart with hitching posts for Amish buggies, the Army base with helicopters and tanks proudly arranged on hills—but I was here for the most unusual thing of all: the local Dynamitron. I was here to make frozen lightning.
Precious metals in your car burn up the dirty exhaust, with no flame to be seen
By Theodore GrayPosted 01.29.2008 at 1:14 pm 2 Comments
More Than Meets the Eye
Invisible propane gas flows, unlit, from a torch. On hitting the rhodium-studded ceramic honeycomb from a catalytic converter, it burns without flame, heating the ceramic red-hot.
To a chemist, burning means the rapid combination of a fuel with oxygen, called oxidation. You might say, for instance, “Oh, no, we didn’t have a fire at the nuclear power plant, we just had a ‘rapid oxidation event,’ ” a phrase that won officials at Three Mile Island the Doublespeak Award in 1979.