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Home Concept Builders Stoichiometry Elemental Measures (a.k.a. Stoikheion-metry) Directions

Elemental Measures (a.k.a. Stoikheion-metry) - Directions

Using the Elemental Measures Concept Builder is quite simple. You will be presented with a balanced chemical equation. From the coefficients and formulas, you must determine the number of atoms of each element on both sides of the equation. You will enter your numbers into the fields in the top portion of the screen under Atomic Scale Analysis. You can enter these numbers directly from the keyboard into the fields. If you are on a touch-screen or mobile device, it may be easier to tap on the small Number Pad icon next to the field and to use our built-in Number Pad in place of the native keypad on your device. Once you complete the atomic scale analysis, proceed to the Macroscopic Scale Analysis. Determine the mass in grams of each element assuming that the coefficients of the equations represent the number of moles of atoms and molecules involved in the reaction. Enter your values of mass into the appropriate fields. We recommend using three significant digits or more as you do your calculations. Finally, there are two conceptual questions to answer. Tap on the boxes to toggle through the three answer options.

You can tap on the Check Answers button at any time. When you do, all currently entered answers will be evaluated. Feedback will be provided in the form of colored fields. Correct answers will be shaded green and will no longer be editable. Incorrect answers will be shaded pink and will be correctable. Once all answers are correct, you will be given the star for that question. There are three questions to answer in each Difficulty Level. Once all three questions are complete, you will receive the Trophy for that level (Task Tracker users only).

Concept Builder Teacher Notes