The key difference between balanced equation and skeleton equation is that balanced equation gives the actual number of molecules of each reactant and product involved in the chemical reaction whereas skeleton equation gives only the reactants of the reaction.
A chemical equation is a representation of a chemical reaction. That means; the chemical equation gives the reactants of the reaction, the end product and the direction of the reaction as well. There are two types of equations as balanced equation and skeleton equation.
CONTENTS
1. Overview and Key Difference
2. What is a Balanced Equation
3. What is a Skeleton Equation
4. Side by Side Comparison – Balanced Equation vs Skeleton Equation in Tabular Form
5. Summary
What is a Balanced Equation?
A balanced chemical equation gives the actual number of each reactant that react with each other and the number of product molecules formed. It is a fully detailed equation which gives the ratios between reactants and products. When calculating a parameter such as the amount of product we obtain from the reaction, we have to use the balanced chemical equation; otherwise, we won’t know how much of reactants reacted to give how much of product.
However, in thermodynamic calculations, this equation doesn’t work when determining the order of reaction because we have to determine the order of reaction essentially via an experimental method. In a balanced chemical equation, the values in front of the molecule are called “stoichiometric coefficient”; stoichiometry is the numerical relationship between reactants and products.
2Na2O ⟶ 4Na + O2
The above reaction is an example of a balanced chemical equation. It gives the decomposition of sodium oxide (Na2O). The normal equation or the skeleton equation of this reaction is Na2O ⟶ Na + O2. When balancing the equation, we can use two methods: inspection method and the oxidation number method.
Inspection method includes balancing the chemical equation by looking at the reactants and products. In this reaction, sodium oxide is the reactant, and it has two sodium atoms and one oxygen atom per molecule. But on the product side, there is one sodium atom and two oxygen atoms. Therefore, first, we can add a stoichiometric coefficient to the reactant side; it is 2. Then, on the reactant side, there are four sodium atoms and two oxygen atom. Since there are two oxygen atoms in the product side as well, we can just add “4” as the stoichiometric coefficient of sodium in the product side to balance this equation. Now the number of atoms in each side is equal; thus, we get a balanced chemical equation.
What is a Skeleton Equation?
Skeleton equation gives the types of reactants involved in the chemical reaction and the end products. However, this does not give the exact ratio between the reactants and products. Therefore, the important details we can get from a skeleton equation are the reactants of the reaction, the products of the reaction and the direction of the reaction. For the above reaction, the skeleton reaction is as follows;
Na2O ⟶ Na + O2
What is the Difference Between Balanced Equation and Skeleton Equation?
The key difference between balanced equation and skeleton equation is that balanced equation gives the actual number of molecules of each reactant and product involved in the chemical reaction, whereas skeleton equation gives only the reactants of the reaction. Furthermore, a balanced equation may or may not contain stoichiometric coefficients while a skeleton equation has no stoichiometric coefficients. For example, the balanced chemical equation for the decomposition of sodium oxide is 2Na2O ⟶ 4Na + O2 while the skeleton equation is Na2O ⟶ Na + O2.
The below infographic summarizes the difference between balanced equation and skeleton equation.
Summary – Balanced Equation vs Skeleton Equation
Balanced equation and skeleton equation are two ways of writing a chemical equation for a particular chemical reaction. In summary, the key difference between balanced equation and skeleton equation is that balanced equation gives the actual number of molecules of each reactant and product involved in the chemical reaction, whereas skeleton equation gives only the reactants of the reaction.
Reference:
1. Helmenstine, Anne Marie. “Balanced Equation Definition and Examples.” ThoughtCo, Sep. 17, 2019, Available here.
Image Courtesy:
1. “Balancing chemical equation – formation of water” By Kvr.lohith – Own work (CC BY-SA 4.0) via Commons Wikimedia