Learn about the properties of acids, bases, pH, and buffers in this comprehensive guide from Khan Academy.

Learn about pH, pOH, and the pH scale in this Khan Academy chemistry lesson.

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2024年2月26日 · 2. Passage and question improvements: Updates to the passages have increased the variety of research studies and graphical data included in Khan Academy passages and have better aligned the passage style with the MCAT exam. The updated passages also include more Skill 3 and Skill 4 questions, to offer extra practice with research and data …

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