Dry ice, or Cardice – as British researchers call it, is a solid form of carbon dioxide. When carbon dioxide is cooled below temperatures of -78.5 degrees centigrade, the gas gets directly frozen into a solid form. -78.5 degrees centigrade is extremely cold, and handling dry ice without proper protection can be very dangerous – could cause frostbite / burns. The point being, it’s extremely cold.
Since it’s too cold compared to something at room temperature, even everyday objects at room temperature can make it vaporize. A simple metal coin at room temperature would feel like a hot pan to dry ice. So, when a coin is shoved into a piece of dry ice, it creates a funny sound, just like water would, on a very hot pan; or, you could say the sound be very much like a hot metal ball being dropped into a cold bath of water (the temperature difference being much less in this case, of course).
This is how it works: The metal piece at room temperature vaporizes some amount of carbon dioxide from the piece of dry ice when it comes in contact. There’s a pressure difference (Bernoulli’s principle) associated with this process and the gas tries to escape. This makes the metal vibrate very fast, creating that funny sound. This is how it sounds…
Metals work best because they have a good thermal conductivity. For the sake of trying it out yourself, if you have a piece of dry ice lying unused, you could dip a spoon in hot water and make it touch the piece of dry ice. A slightly warmer spoon will probably give you a better effect. And then the spoon will be singing…
Hunt for a process to convert a brick of lead into gold was probably the most elusive quest during the olden times when alchemy was around. However, alchemists, who were mostly dismissed as pseudoscientific quacks, actually did some good ground work to make their dream of turning lead to gold into a reality.
And then came the 20th century, when transmutation of one element to another became fairly common. In fact nuclear reactors started working on the same principle. So, besides breaking of uranium atoms and combining of hydrogen atoms to form helium, did it actually become possible to transmute lead into gold using the same process?
Sure it did. Today it is totally possible to make lead (Atomic number 82) release 3 protons to turn into gold (Atomic number 79). Not just in theory, people have actually done it successfully in laboratories. For one, Glenn Seaborg is said to have done it in the year 1951.
To do this, you’d need a particle accelerator. And if you plan to use it as a get rich quick scheme, then you are in for a bad news. Transmuting lead to gold in a laboratory consumes massive amounts of energy, even if you have to do it in extremely minute volumes. So much that the price of doing it exceeds the price of gold by a very big amount. Also, only a very minute volume of gold comes out this way.
To make a single ounce of gold this, it would cost you one quadrillion dollars. You could just buy the same amount for $1300 instead.
Short of time and keeping up with a busy schedule, I looked around for something interesting to learn today and I found this cool video of very interesting experiments that were done with liquid Nitrogen on ScienceDump. There are 11 such experiments that are shown in the video…
The first one is a Liquid Nitrogen explosion, something like this professor did some time back. To demonstrate his students how Liquid Nitrogen expanded, he blew up a container of Liquid nitrogen to toss 1,500 ping-pong balls. [Video]
Is an Aeolipile, or a rocket styled jet engine made using liquid nitrogen A.K.A Hero engine. Liquid nitrogen heats up inside a container, expands and comes out of tiny orifices to create a jet that makes the container spin. A simpler version of it can be done using a ping pong ball (again). [Video]
The third one simply is a demonstration of what happens when you eat a biscuit dipped in Liquid Nitrogen.
Fourth one again is something you’ll have to see to get really impressed by what some solids at very low temperatures can do. A nice demonstration of something similar is done on this video. [Video]
Fifth one! Oh, the Leidenfrost effect. We’ve talked enough about it already. [Here]
Others are all pretty interesting too. The eight one probably takes the cake – brings back a dead creature to life, or does it…. But I won’t spoil them for you. Watch the video now…