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This online course comes from the Open Learning Initiative (OLI) by Carnegie Mellon. “The course includes self-guiding materials and activities, and is ideal for independent learners, or instructors trying out this course package.”" In this course, we'll cover the set of concepts and tools that chemists use to count molecules. We...
This online course comes from the Open Learning Initiative (OLI) by Carnegie Mellon. “The course includes self-guiding materials and activities, and is ideal for independent learners, or instructors trying out this course package.”
" In this course, we'll cover the set of concepts and tools that chemists use to count molecules. We assume that you have had a course in high school chemistry and so are familiar with chemical formulas such as H2O and reactions such as that for the burning of hydrogen in air: 2H2 + O2 → 2H2O. We also assume you've heard of the mole but perhaps are not sure why it is useful. This course is designed to take you from that starting point to a point where you feel comfortable with the primary tools of stoichiometry. This course has two features that may make it somewhat different than what you experienced in high school. The first is that we use a real world application to motivate and set the context for your work. In particular, we've chosen the set of complex issues surrounding arsenic (As) contamination in the drinking water of Bangladesh. We chose this topic because it revolves around the amount of arsenic present in the ground water, an issue that gets to the heart of stoichiometry. The course begins by considering the ways in which chemists discuss the amounts of chemical substances. For instance, when the world health organization says it is unsafe to drink water with greater than 10 micrograms of arsenic per liter, what does this mean? We then shift the emphasis to one of measurement. What are the various techniques chemists use to measure the amount of arsenic in water? What challenges must chemists overcome if they are to provide a low-cost way to determine the amount of arsenic in drinking water?
The second feature that may make this course different from what you experienced in high school is the use of a "virtual lab." Stoichiometry is a powerful toolset that chemists use every day in the laboratory. The virtual lab exercises provided in this course let you use stoichiometry in a similar manner. You will perform experiments that characterize the ability of various powders to remove arsenic from water, and explore various approaches to measuring the amount of arsenic in a water sample."