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Home Concept Builders Stoichiometry Mass Stoichiometry Directions

Mass Stoichiometry - Directions

Using the Mass Stoichiometry Concept Builder is quite simple. Every question has the same format and involves the same task. You will be presented with a balanced chemical equation and a table into which you must enter your answers. There is one given quantity - the mass of a reactant or the mass of a product - in each row of the table. You must calculate the corresponding mass of other reactants and products and enter their values into the table. Numerical answers can be entered directly into the field using your device keyboard or keypad. Users of touch screen and mobile devices may find it easier to enter the numerical answers using our built-in number pad. To access the number pad, tap on the number icon to the right of the field. The number pad will slide in along the right side of the Concept Builder. Use the number pad to enter an anwser. You can tap on a second number pad icon to enter answers for that field or simply tap the Tap to Close button to close the number pad.

You can tap on the Check Answers button at any time. All fields with entries will be checked for accuracy and you will receive immediate feedback. If a field has the correct value, then it will display a green background color and no longer be editable. If a field has an incorrect answer, then it will display a pink background color and can still be edited. There's no limit on the number of attempts. We advise entering answers to three significant digits and using molar mass values with at least three significant digits. Your answer must be within 2% of the keyed answer to be considered correct. Once you have correctly determined all answers, you will receive the trophy for the Difficulty Level (Task Tracker users only).

Concept Builder Teacher Notes