Hydrophobic sand in water [closed]








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[![  ](https://i.stack.imgur.com/ldBj9.gif)](https://i.stack.imgur.com/ldBj9.gif)


Can you please explain this experiment? Why is this happening? 




Directly from Wikipedia under [Magic Sand](https://en.wikipedia.org/wiki/Magic_sand):



> 
> Hydrophobic Sand/Magic Sand is a toy made from sand coated with a hydrophobic compound. The presence of this hydrophobic compound causes the grains of sand to adhere to one another and form cylinders (to minimize surface area) when exposed to water.[1] When the sand is removed from water, it is completely dry and free flowing. Magic sand is also known as Aqua Sand.
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> These properties are achieved with ordinary beach sand, which contains tiny particles of pure silica, and exposing it to vapors of trimethylsilanol $\ce{(CH3)3SiOH}$, an organosilicon compound. Upon exposure, the trimethylsilane compound bonds to the silica particles while forming water. The exteriors of the sand grains are thus coated with hydrophobic groups.
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> Magic sand was originally developed to trap ocean oil spills near the shore. This would be done by sprinkling magic sand on floating petroleum, which would then mix with the oil and make it heavy enough to sink. Due to the expense of production, it is not being used for this purpose. It has also been tested by utility companies in Arctic regions as a foundation for junction boxes, as it never freezes. It can be also used as an aerating medium for potted plants.
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> Magic sand is made in blue, green, or red in colors but appears silvery in water because of a layer of air that forms around the sand, making it unable to get wet.
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Also, see [this informative video](https://www.youtube.com/watch?v=10EnRI80zvk) with explanations and demonstrations.


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