ABOUT FACTS NET Science

You certainly can tell the difference between a solid and a liquid can't you? Of course you can, maybe. Sometimes things are not what they seem in this world and some everyday items may not be what we think they are. Why is this? We are used to thinking in a certain way as humans. For example we believe that if something can be moved around, doesn't get runny and seems solid, then it is solid. But this type of thinking may not lead us to the correct conclusions.

Lets take a well know solid, glass. Hey wait a second, glass is a liquid! Glass only seems to be a solid because it is traveling so slowly that thousands of years would have to pass before you might notice that it was running. As you heat glass and it become hotter it acts more like other liquids. There are people out there that do not believe this and will defend their idea that glass is a solid and may even say it is an amorphous solid but most scientists will disagree with them. I don't think anyone has ever found a puddle of glass anywhere but common usage of glass has not taken place long enough to produce this type of result.

There is a tree in Mexico that looks like it is melting. We all know that trees are solid, don't we? So why does this tree look this way? This is a good question, perhaps the sap inside of it is exerting such force as to extend new growths of the tree downward.

What makes something a solid? It's particles fit closely together. They vibrate and twist but don't move past the particles next to them. There is an attraction between the particles next to each other.

A liquid is different. There still are particles but they are not quite as close together. The particles mix with other particles as opposed to the particles in a solid that don't go past their neighboring particles. This is the main reason why liquids can change shape.

Ice is a solid even though it is composed of frozen water. But there is an unusual feature of ice. If water was frozen at one atmosphere than the resulting ice is less dense that the water it came from. To be exact it is 8% less dense. An atmosphere is the normal pressure we are subject to on Earth.

A liquid was discovered in France, last year, that scientists claim freezes when heat is applied to it. It doesn't take a lot of heat, only a temperature between 45 and 75 centigrade. The liquid is a simple solution of two organic compounds. This material works just the opposite of most solids in that they usually melt when heat is applied.

There is a very strange pseudo solid material that can be easily accessed by almost anyone. No it is not a gift from extraterrestrials. It is the bubbly compound you get when you put dish washing liquid into water. The soapy substance acts like a soft spongy solid. This is commonly know as a foam. There are other foams such as shaving cream and hair mouse. Foam is a form of matter that is not as well understood as solids or liquids.

In 1998 researchers at John Hopkins and Lucent Technologies discovered a solid that shrinks in size when heat is applied to it. It is a ceramic material named zirconium tungestate. But how does this happen? The explanation is that the atoms in the material vibrate at a very low frequency and this causes the material to fold in on itself when heated.

Not every material, whether it be solid or liquid, behaves it the way that you would think that it would. There may be some way to utilize these strange material in some capacity. Maybe there is a use for shrinking ceramic tiles in the space program. Maybe as the tiles shrink they could be made to lock closer into each other to make an even better heat shield for reentering rockets.

No article on solids and liquids would be complete without the mention of the world's lowest density solid. We are talking about Aerogel, a solid that has almost no weight and is made of 99.8% air. It actually looks like some form of smoke in suspension. This unique material has been used to clean spills since it can absorb material. It is on the Mars Rover as insulation.