Professor Xie Yongshu of East China University of Science and Technology teaches his class how to grow their own KCr(SO4)2·12H2O (top) and CuSO4·5H2O (bottom) crystals each year. These pictures shows his students’ work. Xie tells C&EN that crystal chemistry has its own unique charm. In addition to their beauty, he explains, single crystals like these have regular and characteristic geometric shapes. Chromium potassium sulfate crystals, like those in the group shot, are octahedral, while copper sulfate crystals are monoclinic. So along with the colors, purple and blue, respectively, the shape can help give a positive ID for the chemical identity of the crystal.
Submitted by Xie Yongshu
Do science. Take pictures. Win money. Enter our photo contest here.
Related C&EN Content: