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Home Concept Builders Electrochemistry Oxidation-Reduction Directions

Oxidation-Reduction - Directions

Using the Oxidation Reduction Concept Builder is quite simple. There are three activities. Each activity involves a different task. In the first activity - Two Truths and One Lie - you will be presented with three statements regarding oxidation-reduction reactions. Two of the statements are true; one statement is false. You must identify the false statement. You do so by tapping on the false statement to select it. A selected statement is framed in a red box. If you change your mind, tap the statement a second time to deselect it or simply tap on a different statement. As long as you have a statement selected, a Check Answer button will be visible. When you are satisfied with your answer, then you can tap on the Check Answer button. Your answer will be evaluated and your Progress Report will be updated (visible for Task Tracker users only).

In the second activity - Redox Analysis 1 - you will be presented the balanced chemical equation for a simple redox reaction. You must do two things. First, you must assign oxidation numbers to the two elements in the reaction as they exist on the reactant and the product side. There are up and down arrows to tap on to assign oxidation numbers. (Use the Help Me button if you are having trouble.) The oxidation numbers will be as high as +10 or as low as -10. Once all elements have been assigned numbers, a Check Oxidation States button will be visible. Tap to check your assigned state values. Feedback will be given. Correct assignments will be indicated by a green background on the field; these values can't be changed any longer. Incorrect assignments will be indicated by a pink background. You can change these values (turning them to a grey background until checked again). Continue making adjustments until all assignments are correct. Then you will do the second step - identify the element that is oxidized and the element that is reduced. Tap on the Tap Me fields to do so. Tapping toggles between the two options and makes a Check Answer button visible. When you are satisfied with your answer, then you can tap on the Check Answer button. You're allowed only one try. Your answer will be evaluated and your Progress Report will be updated (visible for Task Tracker users only).

In the third activity - Redox Analysis 2 - you will be presented the balanced chemical equation for a redox reaction. You have three tasks to do: 1) Identify the elements that are being oxidized and reduced. 2) Indicate the initial and final oxidation numbers for these elements. 3) And identify the formula of the oxidizing and reducing agent. You can do the three things in any order by tapping on the arrows (for oxidation numbers) or the Tap Me fields for the other tasks. Once you have done all three tasks, a Check Answer button will be visible. If you are satisfied with your answer, then you can tap on the Check Answer button. Your answers will be evaluated and your Progress Report will be updated (visible for Task Tracker users only).


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 activity, you will earn the trophy for that activity.

Concept Builder Teacher Notes