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Home Concept Builders Chemical Reactions Balancing Chemical Equations Directions

Balancing Chemical Equations - Directions

Using the Balancing Chemical Equations Concept Builder is quite simple. There are three difficulty levels. In the Apprentice Difficulty Level, you are presented with a skeleton equation for a chemical reaction. You must identify the coefficients that are required to balance the chemical equation. You do this by tapping on the up and the down arrows above each coefficient location (the grey box). When you do, the coefficient is increased or decreased by 1. There is an Atom Count panel at the bottom of the Concept Builder that updates each time you tap on a coefficient arrow. Once you have entered coefficients for each reactant and product, a Check Answer button appears. If you are confident of your entered answers, then tap on this button. Your answers will be evaluated and your Progress Report will be updated.

In the Master Difficulty Level, you are once again presented with a skeleton equation for a chemical reaction. You must identify the coefficients that are required to balance the chemical equation by tapping on the up and the down arrows above each coefficient location (the grey box). But in this difficulty level, you must also complete an Atom Count for each element. Once you believe that you have balanced the equation, conduct an Atom Count to be sure. Tap on the arrows for each element to indicate the number of atoms of that element on the Reactant and the Product side of the equation. Once you have completed the Atom Count (and the balancing), a Check Answer button appears. If you are confident of your entered answers, then tap on this button. Your answers will be evaluated and your Progress Report will be updated.

In the Wizard Difficulty Level, you must once again balance a chemical reaction when given a skeleton equation. But unlike the Master Difficulty Level, you do not have to complete the Atom Count panel. The panel is there and is interactive to assist in the balancing act. However it is optional and never evaluated when you tap on the Check Answer button.

Your goal is to earn "Stars" and to complete one or more difficulty levels. Stars are earned when you show success on a particular question. If you miss a question then you will have to answer two similar questions correctly before earning a star. Once you show success on all the questions for a particular difficulty level, you will earn the trophy for that difficulty level.

Concept Builder Teacher Notes