What is Mercury?
Diagram of a mercury atom
Thanks to Open Door for this image
Like those atoms, all mercury atoms are made inside older stars that have become supernovas. Mercury is unusual because while most of these heavy atoms are solid at room temperature, the way you think of metal as a solid chunk of something, mercury is instead a liquid at room temperature. This is because mercury's outside electrons don't hold on to other mercury atoms very tightly or very well.
Balls of mercury
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