Gem Mineral

Rubies and Sapphires are different colors of what mineral?

Dihydrogen Monoxide

There's a mock Internet movement to ban Dihydrogen Monoxide.  What is it?
http://dhmo.org/

Brass

Brass is an alloy of what two elements?

Dmitri Mendeleev

Dmitri Mendeleev's achievements include producing the first standard for Russian Vodka and what else?

Penumbra

During what occasional event might you observe a penumbra?

AM and FM

What do the radio terms AM and FM stand for?

World's Largest Organism

The largest organism on Earth is a member of what biological kingdom?

No Moon

What planets in our solar system have no moon?

First Color Photograph

When Scottish scientist James Clerk Maxwell took the first color photograph in 1861, what did he choose for his subject matter?