Johnson Timothy R, Shaffer Tyler A, Holland Lisa A, Veltri Lindsay M, Lucas John A, Elshamy Yousef S, Rutto Patrick K
C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506, United States.
J Chem Educ. 2022 Oct 11;99(10):3590-3594. doi: 10.1021/acs.jchemed.2c00626. Epub 2022 Sep 8.
A laboratory activity was developed to teach freezing point depression and colligative properties to introductory-level chemistry students. The laboratory uses food-grade reagents and is delivered in two units that can be taught in a single 2 hour session or two separate sessions. The total cost of the consumables is 1 USD. In the first part of this two-part activity, students perform measurements on the properties of five salt solutions to better know and understand freezing point depression. In the second part of the activity, students apply their knowledge and understanding of freezing point depression to make ice cream. The ice-cream-making experiment is delivered as a group activity to encourage reflection. Centering this experiment on ice cream allows students to connect properties described in chemistry to everyday life. The solutions used in the experiment are reusable and nonhazardous. The experiment can be implemented in a classroom, in a teaching laboratory, or at home.
开发了一项实验室活动，用于向化学入门级学生教授凝固点降低和依数性。该实验室使用食品级试剂，分为两个单元，可以在一个2小时的课程中讲授，也可以分两个单独的课程讲授。消耗品的总成本为1美元。在这个两部分活动的第一部分，学生对五种盐溶液的性质进行测量，以更好地了解和理解凝固点降低。在活动的第二部分，学生运用他们对凝固点降低的知识和理解来制作冰淇淋。制作冰淇淋的实验作为小组活动进行，以鼓励思考。以冰淇淋为中心开展这个实验，能让学生将化学中描述的性质与日常生活联系起来。实验中使用的溶液可重复使用且无危险。该实验可以在教室、教学实验室或家中进行。
