A different type of 'bucky ball'
Monday 9 February 2015
Most IB teachers and students will know that ‘bucky ball’ is a slang term for the C60 molecule, buckminsterfullerene, which is covered in Sub-topic 4.3 Covalent structures on the syllabus.
However the term is also used for a toy product made out of the rare earth element neodymium. The neodymium spheres or ‘bucky balls’ are magnetic. Neodymium (Ar = 60) is a lanthanoid with the electron configuration [Xe]6s24f4. Although lanthanoids are only briefly mentioned in Sub-topic 3.1 The periodic table, magnetism is covered as one of the properties of the d-block elements in Sub-topic 13.1 First-row d-block elements. Neodymium contains several unpaired electrons around each atom and when it is alloyed with iron and boron it produces a powerful magnetic field. These ‘bucky balls’ make interesting toys as they can be used to make attractive different shapes due to the magnetic attractions between the balls.
Different shapes made from neodymium 'bucky balls'.
Unfortunately neodymium bucky balls are also potentially very dangerous. Older children have used them to mimic body piercings such as tongue studs and there have been many cases of younger children needing hospital treatment after swallowing the balls. They can do considerable damage if they are ingested as the magnetic balls can attract each other through the walls of the stomach and intestine causing the bowel to perforate. The balls were first introduced as a toy in 2009 but in several countries, including the US, Australia and New Zealand they have now been banned on Health and Safety grounds although you can still buy them as ‘anti-stress’ executive toys.
A fun video titled ‘Will it blend?’ by Bendtec has appeared which you could use to illustrate magnetic properties when you teach magnetism, although of course neodymium is not a d-block element. The balls are placed in a blender and the force of the blades and the resulting heat causes them to disintegrate in a shower of sparks. The sparks are caused through friction as the blender blade strikes the balls which produces enough heat for the neodymium to oxidise in the air. The broken pieces then stick together to form the solid mass at the end due to their magnetic properties. Don’t try this yourself either at home or in school, as the fumes of rare earth metals are poisonous.