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Home Concept Builders Chemical Reactions Writing Balanced Chemical Equations Directions

Writing Balanced Chemical Equations - Directions

Using the Writing Balanced Chemical Equations Concept Builder is quite simple. There are three activities. In the first activity - Predicting Products - you will be given a verbal description of a chemical reaction and have to identify the chemical formula of the products. The questions are multiple choice and the choices are listed below the reaction description. You can select an answer choice by tapping on the chemical formulae or on the radio button next to the formulae. When you select an answer, the radio button displays a red center and the text for the chemical formula turn red. If you change your mind, then tap on the answer option a second time to deselect it or simply tap on a different answer option. As long as an answer option is selected, a Check Answer button will be visible. If you are confident of your answer, then tap on this button. Your answer will be evaluated and your Progress Report will be updated.

In the second activity Writing Equations 1 - you must write a balanced chemical equation in three steps. In Step 1, you must identify the basic structure of the equation - that is, the number of reactants and the number of products. Tap on the grey box to toggle through the four choices. Once you have identified your desired choice, tap on the Pick This One button. If you are wrong, you will be given another chance to get it right. If you are correct, you will procede to Step 2. In step 2 you must identify the chemical formula of each reactant and product. There are grey boxes in the skeleton equation that you can tap on. Tapping on a box will toggle through the available choices for the chemical formula. Tap on each grey box until you find the correct formula. Once you are satisfied with your answers, tap on the Check Formula button. Your formulas will be evaluated and feedback will be given. If you have an incorrect formula, then you will be given an opportunity to correct it. If all formula are correct, then you will procede to Step 3. In step 3 you will identify the coefficients for each formula in the equation. Tap on the arrows - up or down - to adjust the coefficients.. Once your are satisfied with your coefficients, tap on the Check Coefficients button. Your coefficients will be evaluated and feedback will be given. If any coeffieint is incorrect, then you will have opportunity to correct them. If all coefficients are correct, you will have completed the questoin and your Progress Report will be updated.

The third activity - Writing Chemical Equations 2 - works just like the second activity. The chemical reactions are a bit more complicated but the process of completing the three steps of each question are the same.


Your goal in the Concept Builder is to earn "Stars" and to complete one or more activities. 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