The transition metals have these properties in common:
* They are metals.
* They form coloured compounds.
* They are good conductors of heat and electricity.
* They can be hammered or bent into shape easily.
* They are less reactive than alkali metals such as sodium, they have higher melting points (but mercury is a liquid at room temperature) and they are hard and tough.
* They have high densities.
The chemical symbol for iron, Fe, comes from the Latin word for iron - ferrum. Iron is the second most abundant metal in the Earth's crust (aluminium is the most abundant metal). The core of the Earth is solid iron, and iron is found in meteorites, but in the Earth's crust iron is found mainly as minerals of iron oxide - hematite, magnetite, goethite and limonite. The mineral which is mostly used as ore for making iron is hematite. Its chemical formula is Fe2O3.
Iron is about 8 times heavier than water (its relative density is 7.87). When iron is exposed to the air it starts to turn back into iron oxide and the red powder that forms on the surface of iron is what we call rust. You may have seen rust on old cars or old iron sheds or roofs. To make iron stronger and less likely to rust it can be combined with carbon and other elements to make steel.
The mineral magnetite is very magnetic, and if you dangle a piece on a length of string it will orient itself north-south. Iron and some alloys of iron are also magnetic.
The Properties of Iron
iron oxides: eg hematite and magnetite