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Home Concept Builders Chemical Reactions Balancing Chemical Equations Help Help 5

Balancing Chemical Equations - Questions 5 Help

A balanced chemical equation shows the number of particles of each substance involved in a chemical reaction. Such an equation includes formulas and coefficients. The formulas include symbols for each type of atom in the substance. The coefficients are the numbers present in front of the formulas. The act of balancing a chemical equation involves selecting the lowest possible set of coefficients that would provide the same number of atoms of each element on the reactant and the product side of the equation.

There are two questions in this Question Group. The two questions are very similar or are of similar difficulty level. The question below is one of the questions.

Version 1:

Identify the lowest possible whole number coefficients that balance the chemical equation.
 

MnI3 → Mn + I2

To be successful with this question, you need to know what a balanced chemical equation involves. You also need to have a good strategy for how to balance a chemical equation. The two infographics below describe these two ideas. Study the graphics, giving particular attention to the Step-by-Step Balancing Method and the Example in the second infographic. Some specific information regarding this question are provided after the second infographic.

 





 

Some Specifics About This Question Group

The two versions of questions in this Question Group are similar. There are two elements in the skeleton equation. One of them (Mn or Pa, depending on the version) is already balanced. The other element - I - is not balanced. You will need to place coefficients in front of the reactant and product formulae containing iodine. Look at the I subscripts in these two formula and ask yourself, what coefficients must be placed in front of these two compounds so that the number of iodine atoms is the same on the left and the right side of the yields arrow? Once you figure out the set of two coefficients that are needed to balance the element I, you are almost done. Complete the balancing act by placing a coefficient in front of Mn (or Pa) in order to balance the second element.
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