Have you checked out Magic Sand?
How can something submerged in water stay dry?
How can something submerged in water stay dry? When ordinary sand gets wet, the result is a clumpy mess. However, “Magic Sand” begins as normal looking sand, until it’s coated with a substance that repels water. This special coating keeps the sand dry even after it has been dumped into a container of water.
We had so much fun with magic sand.Regular Sand vs. Magic Sand
Have your students compare the difference in how regular sand and Magic Sand acts. If you put regular sand in water, it immediately sinks, but a thin layer of Magic Sand will float on the surface of the water. The surface of the regular sand grains is made wet by water, which means that water molecules are attracted to sand grains. Magic Sand is regular sand that has been coated with an oil-like substance so it is water-hating and stays apart from it, floating on the surface. Surface tension of the water also helps to make Magic Sand float.
We love that it's technical name is hydrophobic (water-fearing) sand.
It is sand that stays dry, even under water.
It is colored sand that is treated to make it resistant to water but the kids just think it is a lot of fun.
Have your students compare the difference in how regular sand and Magic Sand acts. If you put regular sand in water, it immediately sinks, but a thin layer of Magic Sand will float on the surface of the water. The surface of the regular sand grains is made wet by water, which means that water molecules are attracted to sand grains. Magic Sand is regular sand that has been coated with an oil-like substance so it is water-hating and stays apart from it, floating on the surface. Surface tension of the water also helps to make Magic Sand float.
We love that it's technical name is hydrophobic (water-fearing) sand.It is sand that stays dry, even under water.
It is colored sand that is treated to make it resistant to water but the kids just think it is a lot of fun.
It occupied their attention for quite a long time
Some years ago we experimented with food coloring coloring water and the difficulty of mixing of oil and water. Oil and vinegar salad dressings have the difficulty of hydrophobia and need to be shaken up before using. Sand is naturally water-loving or "hydrophilic". But Magic Sand is regular sand that has been coated with an oil-like substance that is water-hating or "hydrophobic." making up all sorts of ways to experiment.
Have your students pour a small amount of the Magic Sand in a cup of water, but then add about 12 drops of liquid detergent to the water and use a spoon to stir the mixture. It will now behave like regular sand and sink. Soap breaks down the oil coating on the sand and lowers its hydrophobic properties.
The coating on Magic Sand is like Scotchguard, which is sprayed on fabric to protect it from stains. Magic Sand was originally developed as a way to trap oil spilled from oil tankers near the shore. The idea was that when Magic Sand was sprinkled on floating petroleum, it would mix with the oil and make it heavy enough to sink. This would prevent the oil from contaminating beaches. However, it is not being used for this purpose, perhaps because of the expense of making Magic Sand. Another potential use of Magic Sand is to bury junction boxes for electric and telephone wires in the Arctic in order to protect the utilities from the extreme cold temperatures but make it easy to dig up for repairs. Normal earth is frozen so hard because of moisture content and it is difficult to dig. However, Magic Sand remains dry and is easy to dig, regardless of how cold it is.
