Solids will hold their own shape. Even if you grind up that solid, those small pieces still have the molecular shape as the larger piece. A solid of a certain element can have very different shapes, such as carbon being in charcoal and diamonds. This all depends on how the individual atoms line up into a solid. The molecules can arrange in a very random pattern, or in very geometric shapes. There are 6 basic shapes. If you look at a crystal of sugar and one of salt, you may see a difference. Salt tends to be very cubic. Sugar will almost look cubic, but if you look carefully, you see the cube is tilted. This explains how crystals can form so many wonderful shapes. The solids with random patterns tend to be much softer and slowly go from solid to liquid. The crystal style of solid tends to be much harder and melt at one specific temperature.

If you need something to fill up a certain shape, you usually want to use a liquid. This state has no shape of its own, but is fairly easy to contain. It gets affected by gravity more than solids do. It is hard to compress a liquid, though. Some fun things about liquids are they have something called "surface tension" and can do "capillary action". Try putting a drop of water on the counter. If the counter is clean, it will make a little bead. That is because the surface tension of the water is holding all of the water molecules together, like its own little container. Now put a little bit of soap in that drop, with a toothpick. Soaps break up the surface tension of water, making it much more relaxed. Can you guess what happens to the water? This gets used in ice cream, also. You know some of those ingredients you can't pronounce on the ice cream box? At least one of those are to make the melted ice cream spread evenly through your mouth.

Have you ever seen how water will flow upwards through a straw? Even without sucking on it? This is because of liquids capillary action. Just like there are attraction forces inside the drop of water, there are some attraction forces between the water and a container or straw. If you used colored water in a clear straw, you would see that the water forms kind of a U shape where it touches the straw. The straw sides are grabbing a hold of the water even before it reaches that level. If you get a thin enough straw, the water will rise all the way up by itself, without sucking on it at all! The fascinating thing is that not all liquids are attracted to the container walls. If you Mercury in a straw, it would look more like an N than a U. Mercury would much rather hang around with itself than any container. Capillary action is how plants get water and nutrients to its leaves.

Gases are the most easygoing of all the states. The arrangement of molecules is far apart, and really random. This is the state that is most susceptible to even tiny changes in temperature, pressure and volume. They fill an empty shape by bouncing atoms off the surface of the container, and will mix with almost anything in this state. They will mix with other gases, liquids, even some solids, but mixing with solids isn't as common. A few examples of common gas mixtures are carbonated soda and charcoal filters. Soda is made by bubbling carbon dioxide gas into a liquid, usually a flavored syrup in water. Charcoal is well known for collecting and holding gasses in its cavities, so is a good example of the solid/gas mixture.

Plasma

There is a 4th state, but it is rarely found in nature. Mankind is making use of it a lot more lately, however. It is the state that is responsible for the northern lights and ball lightning. It's called plasma. It is superexcited gas. So much energy has been pumped into the gas that it forms individual atoms, ions and even free electrons! That is what makes them so rare and reactive, because electrons don't usually go off on their own unless they have someplace specific to go. This is what is happening when you turn on a fluorescent light. A shot of electricity is exciting the gas inside, it goes into plasma, and you see the side effect - light. The type of gas that turns to plasma chooses the color of light that comes off. Neon tends to be red, but if mixed with argon and mercury, it can make green and blue. Stars are made primarily of plasma, and our sun has plasma bursts. You may be most familiar with plasma displays, though. You know, those new flat panel TV's and computer screens? For more details on exactly those work, you may want to check out this webpage.

Water is another easy example of how states change. You can find it as ice, liquid, or steam. We know the conditions to make water change from one state to another and we use this frequently. If we want to freeze something with water in it, we know we have to go down below 32 degrees. Suppose we needed to freeze something but we could only get the temperature down to 40 degrees? There are some liquids that freeze, turn into solid, at this temperature. Earlier we discussed how liquid nitrogen turns to a gas at a very low temperature, and how that can be used to freeze other matter. Remember the Dipping Dots ice cream?