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Molecules are made of atoms held together by chemical bonds. The water

Nanotechnology is not about simply making devices smaller. The field uses the fact that nano size materials can have different properties than their larger counterparts. Color, hardness, melting point, and conductivity are all some of the properties that can change as the material become nano sized. One physical characteristic that can lead to these changes is the increased ratio of the surface area to volume. Surface area is all the area that is on the outside--surface--of the material. Volume is the amount of three-dimensional space taken up by a material. As a material shrinks, its surface area increases compared to its volume, In the nano size, this ratio can increase dramatically, which can lead to different reactions. Gold nano particles, for example, can appear a reddish color and turn liquid at room temperature. It is the arrangement of the atoms and molecules that gives materials its properties. Diamonds and the lead of pencils (graphite) are both made of up carbon molecules. In diamonds, the arrangement and bonds of the carbon atoms make it hard and clear. Graphite is dark and relatively soft. If researchers can pluck individual atoms and decide how to arrange them, they can determine the property of the material. One nano scale material that was discovered in 1991 is also made of pure carbon. Carbon nano tubes are threads of carbon and the arrangement of its carbon makes it light, flexible, and stronger than steel.