Nanoscience

Working with nanoparticles is called nanotechnology

A nanometre, 1 nm, is one billionth of a metre (or a millionth of a millimetre). Nanoparticles range in size from about 100 nm down to about 1 nm. They are typically the size of small molecules, and far too small to see with a microscope.

Properties and uses of nanoparticles

Nanoparticles have a very large surface area compared with their volume, so they are often able to react very quickly. This makes them useful as catalysts to speed up reactions. They can, for example, be used in self-cleaning ovens and windows.

Nanoparticles also have different properties to the same substance in normal-sized pieces. For example, titanium dioxide is a white solid used in house paint and certain sweet-coated chocolates. Titanium dioxide nanoparticles are so small that they do not reflect visible light, so cannot be seen. They are used in sun screens to block harmful ultraviolet light without appearing white on the skin.

In addition to new cosmetics such as sun screens and deodorants, nanoscience may lead to the development of:

• New catalysts
• New coatings
• New computers
• Stronger and lighter building materials
• Sensors that detect individual substances in tiny amounts

Now try a Test Bite.

Read on if you're taking the higher paper.