Items were developed based on an existing learning progression for acid–base chemistry. We used the Rasch rating scale model for validation and to gain understanding of how students at different ability levels conceptualize the topic. We then used latent class analysis (LCA) to place students ...
Chemistry is an essential branch of science that explores matter’s composition, structure, and properties and the changes it undergoes during chemical reactions. It plays a vital role in daily life, from medicine and environmental sustainability to technological innovation and industry. When it comes ...
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“The concerns about Teflon primarily relate to PFOA (perfluorooctanoic acid), which was historically used in manufacturing Teflon coatings until 2013,” said David Nadler, Ph.D., a professor in the Occupational Health and Safety graduate program at New York Institute of Technology. Per- and poly...
Learn how to calculate the pH a strong acid-strong base solution, and see a few examples that walk through sample problems step-by-step for you to improve your chemistry knowledge on calculating the pH of a strong acid-strong base solution.
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Learn how to find the predominant form of an acid or base, and see examples that walk through sample problems step-by-step for you to improve your chemistry knowledge and skills.
We propose explicit and implicit approaches for the teaching of acid-base chemistry based on research into the history and nature of science (NoS). To support these instructional proposals, we identify four rationales for students to understand acid-base processes: daily life, socio-scientific, curr...
a sealed glass tube containing a twist of paper tipped with phosphorus. When the tube was broken, air rushed in, causing the phosphorus self-combust. An even more hazardous device, popular in America, was the Instantaneous Light Box — a bottle filled with sulphuric acid into which sp...