WEBVTT
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in strict geometric calculations. It's useful to create a
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roadmap to describe how to go from one quantity to
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another. So if, for example, we have
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25 grams of a an excess amount of be reacts
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to form, see, we can calculate how much
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C should form in grants. The idea that something's
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in excess means that the only quantity that determines our
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product is the initial amount of a. So if
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we have a mass that we start out with 25
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grams, the first thing that we need to do
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is to change that two moles of a and we
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do that by dividing by the molar mass of A
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A. Once we have moles of a we confined
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walls of C. We do that using the mole
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ratio from the balanced equation and the last step.
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Once you know your moles of See, we can
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change it to grams of C using the molar mass
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of C. And this time we multiply. So
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using the road map, it sets up your calculation
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for how to convert from one quantity to another.
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In a chemical reaction