Science - icy orbs

 

This was a really fun experiment. Water molecules are bonded together when they are ice - a solid. Salt crystals are made of sodium ions and chloride ions. The sodium ions break apart the ice turning it into water, and the chloride ions cling to water molecules that have broken free from their regular pattern.

This is why specially designed lorries spread ice on roads in freezing temperatures. The salt melts ice and snow but also prevents ice from forming. The salt lowers the freezing point of water.

The food colouring made interesting patterns as the salt made its way through the ice.