On the second episode of "Tiangong Class" this Wednesday afternoon, astronauts on board China's space station demonstrate the crystallization process, how surface tension works, and also try separating oil and water in space. What do these processes look like on Earth? Why are they conducting these experiments in space, and how are they significant in our daily lives? Join Chen Zheng from Beijing Jiaotong University and David Evans from Beijing University of Chemical Technology on "The Chat Room" to take part in these experiments and learn more about the science behind them.

Editor's note: The experiment is risky, and it should be conducted under the guidance of professionals.