Here on Earth we live in an atmosphere containing a reactive compound called oxygen. It’s necessary for life as we know it to exist! It also reacts with most materials. For example, metals form oxides on their outside surfaces where they touch oxygen.
The way we think of metals has a lot to do with what this oxide is like. Everyone knows that iron rusts. This is because Fe2O3 is the oxide formed on iron, which is reddish and powdery and sticks to the iron surface. On the other hand, osmium forms osmium tetroxide (“osmium with four oxygens”)  OsO4 which is volatile and evaporates into the air. Since it’s a gas you can smell it, and this is why osmium has a name that basically means “a smell.”

Here on Earth we live in an atmosphere containing a reactive compound called oxygen. It’s necessary for life as we know it to exist! It also reacts with most materials. For example, metals form oxides on their outside surfaces where they touch oxygen.

The way we think of metals has a lot to do with what this oxide is like. Everyone knows that iron rusts. This is because Fe2O3 is the oxide formed on iron, which is reddish and powdery and sticks to the iron surface. On the other hand, osmium forms osmium tetroxide (“osmium with four oxygens”)  OsO4 which is volatile and evaporates into the air. Since it’s a gas you can smell it, and this is why osmium has a name that basically means “a smell.”