Chemistry Curiosity Club (CCC) is a chemistry club that has been established at SCIE for seven years. It attracts a group of individuals who are passionate about chemistry and enjoy discussing chemical knowledge.
As “scientific research experts” who are extremely enthusiastic about practicals, the three presidents of CCC immediately began planning practical activities as soon as they took office. After nearly a month of planning and preparation, we successfully got the opportunity to hold a practical through the experienced president Richard.
Our practical this time was carried out based on the Tollen’s test. This reaction is a chemical reaction in which a solution of silver (Ag) compounds is reduced to metallic silver. Because the generated metallic silver adheres to the inner wall of the container and is as bright as a mirror, it is also called the silver mirror reaction. Since the Tollen’s test can take advantage of the fact that aldehydes are easily oxidized and ketones are not easily oxidized, it is often used in the laboratory for qualitative testing of aldehydes and ketones.
The experiment has certain safety risks. Thus, President Richard, who led this practical, conducted multiple tests before the practical began to ensure that the protocol steps were safe and effective. The entire experiment was carried out smoothly under the supervision of our club supervisor Ms. Gong.
During the process,difficulties were encountered, but we overcame them one by one: due to the reaction of residual chloride ions in the container with silver ions forming precipitates, some members reported that the liquid which should have been clear turned into a turbid white color. By repeatedly washing the container with nitric acid solution, the solution obtained after repeated experiments became clear and transparent; after the mixture was heated in a water bath, some members reported that the liquid in the container where the silver mirror should have appeared still stubbornly remained transparent. Through “rebellious” attempts, we came up with a “bold” addition method that used a lot more solvent than required by the protocol. In the end, the tenacious mixture was impressed by our imagination, and a beautiful silver mirror appeared on the wall.
Seeing students of different grades and who had never met before gradually become familiar with each other and sharing their unique insights, we felt that this is the meaning of the club. Gathering together because of the interest in Chemistry, speaking freely in the search for truth, sharing ideas and experiences generously, having heated discussions with other members, and learning about novel viewpoints are all rare and valuable experiences in extracurricular learning. The spark that flashed across the iris at the same time after getting the best solution is the enlightenment after understanding the knowledge, and the joy after the exchange of ideas.
What our member says…
Last month, The CCC organized a fun experiment about plating a silver mirror on glass on October 30th. Being a chemistry enthusiast, this was the event that I absolutely HAD to join. We arrived at the lab shortly after the end of afternoon’s class, but I forgot my lab coat, went back to take it, and unfortunately missed the group photo.
The process of finding which procedure worked best was quite fun.
I first followed the instructions given, but it didn’t work really well. I have done the silver mirror experiment before, so I tried again using my own procedure. This also didn’t work, mainly because the chemicals had a lower concentration. I got a little frustrated, and decided to stop to think for a better solution. Finally, I came up with a procedure that incorporated my experience with the given instructions.
After two more tries and slight adjustments, I made a perfect silver mirror!Almost the whole vial was covered in a uniform layer of silver, and there were no scratches or bubbles. I was quite satisfied initially, but upon closer inspection, the mirror wasn’t that perfect as I thought it would be. The coating was so thin that it almost looked translucent under bright light.
I decided to take the risk and do something that nobody had done before: Make another layer of silver below the first layer. After adjusting the reaction mixture so that it won’t break down the first coating, I took a deep breath, prepared myself for a massive failure, and plunged the vial into the water bath. Immediately, I see the coating gradually turning opaque. It actually worked! The thrill of seeing my own ideas work flooded my body, expelling the fatigue of a whole day’s worth of classes.
- Article / Nicole Zhou, Torres Fan, Richard Zhang, Juan Zhang
- Pictures / Chemistry Curiosity Club
