What is the common name for iron oxide, which appears after iron has been exposed to air and water?

More Questions:

What stopper, necessary for champagne, did medieval monks invent?

What is Lepidopterology the study of?

Which US state is sometimes referred to as the Beaver State?

What island was once called Van Diemen's Land?

What French scientist discovered that many diseases are caused by germs?

What sensory organ do starfish have at the end of each arm?

Which Space Shuttle broke apart during re-entry in February, 2003?

Approximately, how long does it take light from the Sun to reach the earth?

What is the more common term for sternum?

The Don McLean song that begins "Starry starry night" is actually named for what painter?

Which members of the "Bee Gees" were twins?

What was known as the Lady of the Lamp?

In Roman numerals, what number does "D" represent?

Which famous actor is honored with a statue in Leicester Square?

According to most sources, where is the world’s tallest unclimbed unclimable mountain?