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Which Powder is It?


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In this chemistry challenge, learners identify an unknown white powder by comparing it with common household powders. Learners first explore what happens when baking soda, baking powder, and washing soda are mixed with water, vinegar, and PHTH (the indicator phenolphthalein mixed with alcohol and water). Learners then work to identify the unknown based on how it reacts with the known solutions. This is a simplified form of "qualitative analysis," which was historically an important approach chemists used for identifying unknown samples. Less

Learning Registry Activity


    Topics and Grades

    Grade: TK/K to 9

    Topics: Chemical Reactions & Stoichiometry, Physics, Chemistry, Earth & Space Science

    Resource Pedagogy

    Resource Type/Classification:

    • Teacher Materials

    Tool for: Students