In this demonstration, we will see gallium melt at skin temperature and on a hotplate and we will see liquid gallium cast in a strawberry mold, highlighting the important differences between liquids and solids.
Gallium is a special metal. Out of the nearly 100 metal elements, only two are liquids at
body temperature: gallium and mercury. Completely nontoxic, gallium is rarely used in its pure
form, except to make joke spoons that melt in your tea.
Gallium is the perfect visual example of the properties of solids and liquids. When molten,
gallium will take the shape of its container;
but, given enough time to cool, it will hold its shape.
Why does gallium have such a low melting point?
On the periodic table, gallium is in the same group as aluminum and indium and sits next to
zinc and germanium. All these other metals have relatively high melting points.