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When iron rusts

2002

i found some info on this so here it is When iron rusts, basically what happens is that it oxidizes to form Fe2O3. In order for this to happen, electrons have to leave the iron atoms so that it can get positive charge and bond with oxygen. ("oxidize" comes from the element name "oxygen"). This process happens much more quickly when you have tap water, because there are other particles that have electrical charge floating around in it, such as calcium, magnesium, chlorine, and fluorine ions. When these ions are present, it allows the electrons to leave the iron much more easily, and rust more easily.

By the way, the chlorine that is used to treat water is Cl2, or chlorine gas. By the time the water reaches your faucet, this stuff has reacted to form chloride ions. Although chloride ions are not corrosive, they do allow iron to rust more easily.

Carissa
- Manchester, Missouri, USA