At first thought, you might think that an ice cube sitting at the very top of a glass would eventually melt and spill over the sides, but is this what really happens? Experiment and find out!

What you’ll need:

A clear glass
Warm water
An ice cube
 

Instructions:

Fill the glass to the top with warm water.
Gently lower in the ice cube, making sure you don’t bump the table or spill any water over the edge of the glass.
Watch the water level carefully as the ice cube melts– what happens?
 

What’s happening?

Even though the ice cube melted the water doesn’t overflow.  When water freezes to make ice it expands and takes up more space than it does as liquid water (that’s why water pipes sometimes burst during cold winters). The water from the ice takes up less space than the ice itself. When the ice cube melts, the level of the water stays about the same.