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Knowledge and Skills Statement

Science concepts. The student understands and applies various rules regarding acids and bases.

any substance that in aqueous (water) solution tastes sour, changes blue litmus paper to red, reacts with some metals to liberate hydrogen, reacts with bases to form salts, promotes chemical reactions (acid catalysis), and has a pH less than 7

any substance that in aqueous (water) solution is slippery to the touch, tastes bitter, changes the color of indicators (e.g., turns red litmus paper blue), reacts with acids to form salts, promotes certain chemical reactions (base catalysis), and has a pH greater than 7

Research

Hurtley, Stella. "Ambiguous Acidity." Science 306, no. 5697 (2004): 781. doi: 10.1126/science.306.5697.781. https://www.proquest.com/docview/213610009?pq-origsite=gscholar&fromopenview=true&sourcetype=Scholarly%20Journals

Summary:  Acidic strength is often broadly defined as the ease with which an acid loses [H+] to a base. Stoyanov et al. show that in nonpolar media, where acid and base stay closely associated after reacting, the relative strength of two acids varies with the base. The data suggests that the acidity of HX depends not only on the stability of [X-] but on direct molecular interactions between X and the base.

Research

Jiménez-Liso, Maria Rut, Luisa López-Banet, and Justin Dillon. "Changing How We Teach Acid-Base Chemistry." Science & Education 29, no. 5 (2020):1291-1315. https://doi.org/10.1007/s11191-020-00142-6

Summary:  To support explicit and implicit approaches for the teaching of acid-base chemistry, we identify four rationales: daily life, socio-scientific, curriculum, and history of science. The extensive bibliography on misconceptions at all educational levels justifies the need for a change from the usual pedagogical approaches to teaching the acid-base domain (traditionally involving conceptual-focused teaching) to a deeper and more meaningful approach that provides (implicitly or explicitly) a chance to reflect on how scientific knowledge is constructed.