Report on transition elements?

Question

I have to do a report and presentation on "The properties and usage of selected transition elements". I selected iron, cobalt and nickel because somewhere I read that they where special. I wanted to start off by describing some sort of technology that uses iron, cobalt and nickel and then describe the role of each and then describe the properties that make them so usefull. The problem is, I don't know of any such technology, If anyone knows of one or has any general tips or suggestions for me I would appreciate it.

BTW: the presentation is on monday so I don't have time for anything overly elaborate.

Answer 1

They are used as catalyst. I think this is so because they contain d-orbitals and the substances taking part in the reaction forms dative bonds with the catalyst. The bonds of the reactants weaken and break and the product can now be formed.

Answer 2

I recommend that yiou concentrate on cobalt, because its chemistry is so interesting. In particular, cobalt(III) has a "stiff" coordination sphere. That is, once you get the 6 substituents in place at the corners of the octahedron, they stay there unless you use certain well-defined reactions to exchange them for others. Also, you have possibilities for cis-trans isomers and optical isomers. There is a marvelous variety of colors for isomers, because some ions are inside the coordination sphere and others are counterions outside.