BEAUTIFULCHEMISTRY.NET / SCIENCE PHOTO LIBRARY BEAUTIFULCHEMISTRY.NET / SCIENCE PHOTO LIBRARY
Iron silicate crystals. These crystals have grown as a result of iron (III) chloride being added to a solution of sodium silicate (also known as water glass). The salt partially dissolves in the water and its ions react with silicate ions to form a thin layer of insoluble iron silicate. This layer is semi-permeable, and the more concentrated salt solution inside the tube pushes outwards due to osmosis. This bursts the tube, releasing more salt solution and forming a new tube, and the process continues. As the pressure is greater further down the water column, the tubes grow upwards.
Model release not required. Property release not required.