Experts from the Chinese Academy of Sciences guide elementary school students to conduct magical experiments and create "Elephant Toothpaste" on the first day of summer vacation. Elephant | Course | Toothpaste
Today is the first day of summer vacation for primary and secondary school students. A unique chemistry class was held in Room 901 of Shanghai Science Hall. The students are more than ten primary school students registered through the official account of Shanghai Association for Science and Technology and Kemeng Culture Communication Company, and the teachers are chemical experts such as Li Qi, senior experimenter of the Chinese Academy of Sciences Shanghai Institute of Organic Chemistry. In class, experts from the Chinese Academy of Sciences guided students to complete the "Elephant Toothpaste" experiment, allowing them to experience the magic of chemistry.
In May this year, the "Shanghai Science Popularization" Shanghai Science Popularization Trading Board, which is operated by the Shanghai Technology Exchange, completed its first transaction. The "Magic Chemistry Science Popularization Offline Curriculum and Courseware Development" project of the Chinese Academy of Sciences Shanghai Institute of Organic Chemistry was transferred to Shanghai Kemeng Culture Communication Co., Ltd. in the form of technology service transaction, with a transaction volume of 50000 yuan.
The characteristic of this science popularization project is to combine current social hotspots, take chemistry issues around us as the starting point, supplemented by a large number of interesting experiments, and guide students to understand and explore chemistry through experiential teaching. After completing the transaction, through the cooperation of the transfer and transferee, offline scientific thinking training course materials will be formed to cultivate the scientific literacy and innovative thinking of primary and secondary school students.
Under the guidance of the Shanghai Association for Science and Technology, the Shanghai Science Popularization Center, in collaboration with the Kemeng Culture and the "Magical Chemistry" offline course project team of the Shanghai Institute of Organic Science, Chinese Academy of Sciences, held the "Elephant Toothpaste" experimental public welfare course today at the renowned Shanghai Science Hall. This is the first offline activity after the first transaction of the science popularization project.
"Do you know what chemistry is?" "Opening a soda can produces a lot of bubbles. Is this a chemical reaction?" In class, Teacher Li Qi asked two questions to elementary school students. Although chemistry classes are not offered in primary school, children who raise their hands answer correctly. For example, a child said, "Bubbling cola is not a chemical reaction because it does not produce new substances." After some questioning and answering, Teacher Li explained the definition of chemistry through a large screen: "Chemistry is the science of studying the composition, properties, structure, and changes of substances at the molecular and atomic levels, and creating new substances."
Subsequently, Teacher Li demonstrated the "Elephant Toothpaste" experiment. I saw him pour two transparent solutions, A and B, into a cola bottle one after another, each with 100 milliliters, and then pour 100 milliliters of dishwashing detergent into the cola bottle. Immediately, the chemical reaction took place - the mixed transparent solution turned yellow, and white foam gushed out. At first sight, it looked like beer, which was called "elephant toothpaste".
"Boys and girls, the amount of foam in this experiment is not enough. Let's make more toothpaste for the elephant." Teacher Li said and began the second experiment. The steps were the same as the first experiment, except that the amount of dishwashing detergent poured doubled and increased to 200 milliliters. This made the chemical reaction much more violent than that of the first experiment. A thick white foam gushed out of the Coke bottle at a height of nearly half a meter, causing a cry of surprise from the children.
After watching the magical experiment done by the teacher, the children started DIY. Wearing experimental work clothes, disposable gloves, and goggles, under the guidance of the teacher, they measured the volume of two transparent solutions and dishwashing detergent using a measuring cylinder, and then poured them into a cola bottle one after another, successfully creating "Elephant Toothpaste".
What is the scientific principle of this chemistry experiment? After the children finished the experiment, Teacher Qi revealed the answer - these two solutions are hydrogen peroxide and potassium iodide, respectively. Hydrogen peroxide is a compound of hydrogen and oxygen. When it encounters a catalyst such as potassium iodide, the decomposition rate of hydrogen peroxide will significantly accelerate, producing a large amount of oxygen. When these oxygen overflows into the solution mixed with foaming agent, a large amount of foam will be produced and gush out of the solution.
At the end of the course, Jiang Xuefeng, an outstanding figure in mass science communication in Shanghai and a professor from the Department of Chemistry at East China Normal University, gave a review of the event. The event organizer also asked parents of students attending classes to provide feedback through a questionnaire. The Popularization Department of the Municipal Association for Science and Technology stated that the next step will be to deepen cooperation with scientific research institutions, universities, and enterprises, and provide more high-quality science popularization education resources to the public.
