Spend some time with the kids trying out a series of fun and educational salt science experiments that will delight any child.
From growing crystals, to changing the rate of melting ice and increasing the density of water to make objects float, these experiments allow you and your younger one to explore the science of ordinary table salt. And the good news – salt experiments can be completed at any time, with little preparation or clean up.
Many salts show a large increase in solubility with temperature. Some solutes like sodium chloride in water exhibit solubility that is fairly independent of temperature. It is most likely the evaporation of the water is the main effect here.
Oil is less dense than water so it rises to the surface, while salt is denser than water and sinks to the bottom. When the salt is added, blobs of oil attach to the grains and sink. The salt then dissolves and the oil returns to the top.
Dissolving salt in water lowers the temperature at which the water freezes. Salt, when placed on top of a melting ice cube, will dissolve in the water that melts first and the brine (dissolved salt) lowers the melting temperature of the ice it’s in contact with.
Salt water is denser than ordinary tap water, the denser the liquid the easier it is for an object to float. When the object is lowered into the liquid, it drops through the normal tap water until it reaches the salty water. It’s at this point that the water is dense enough for the object to float.
Separate Salt and Pepper
When a comb is rubbed against a cloth or balloon, it becomes negatively charged. The salt and pepper are both positively charged, which means they will be attracted to the static from the comb. When the comb is placed above the mixture, the pepper will fly up and attract, whilst the salt will remain in place.