Q. 7.36 - An Introduction to General, Organic, and Biological Chemistry

Question

Determine whether each of the following chemical equations are balanced or not balanced:

a. $PC{l}_3\left(s\right) + C{l}_2\left(g\right) \to PC{l}_5\left(s\right)$

b. $CO\left(g\right) + 2H_2\left(g\right)\to C{H}_{4}O\left(g\right)$

c. $2KCl{O}_3\left(s\right)\to 2KCl\left(s\right) + O_2\left(g\right)$

d. $Mg\left(s\right) + N_2\left(g\right)\to M{g}_3{N}_2\left(s\right)$

Step-by-Step Solution

Answer

a)  The reaction is balanced.

b)  The reaction is balanced. 

c) The reaction is not balanced. 

d)  The reaction is not balanced. 

Part (a) Step 1: Given information

We have been given four equations and we have to check which equation is balanced.

Part(a) Step 2: Explanation

To determine whether or not an equation is balanced, we apply the procedures below:

• Divide each molecule into its constituent atoms. Calculate the number of each type of atom in each molecule.
• Count the number of atoms of each kind on each side of the equation (for the reactants and the result).
• The element is balanced if the number of atoms on both sides of the equation equals one.
• If all of the elements are balanced, the equation is balanced.

We get what we want by following these steps.

$PC{l}_3\left(s\right) + C{l}_2\left(g\right) \to PC{l}_5\left(s\right)$

This reaction is balanced.

Part (b) Step 1: Given information

We have been given four equations and we have to check which equation is balanced.

Part(b) Step 2: Explanation

To determine whether or not an equation is balanced, we apply the procedures below:

• Divide each molecule into its constituent atoms. Calculate the number of each type of atom in each molecule.
• Count the number of atoms of each kind on each side of the equation (for the reactants and the result).
• The element is balanced if the number of atoms on both sides of the equation equals one.
• If all of the elements are balanced, the equation is balanced.

We get what we want by following these steps.

$CO\left(g\right) + 2H_2\left(g\right)\to C{H}_{4}O\left(g\right)$

The reaction is balanced.  

Part (c) Step 1: Given information

We have been given four equations and we have to check which equation is balanced.

Part(c) Step 2: Explanation

To determine whether or not an equation is balanced, we apply the procedures below:

• Divide each molecule into its constituent atoms. Calculate the number of each type of atom in each molecule.
• Count the number of atoms of each kind on each side of the equation (for the reactants and the result).
• The element is balanced if the number of atoms on both sides of the equation equals one.
• If all of the elements are balanced, the equation is balanced.

We get what we want by following these steps.

$2KCl{O}_3\left(s\right)\to 2KCl\left(s\right) + O_2\left(g\right)$

The reaction is not balanced.  

The balanced reaction is:

$2KCl{O}_3\left(s\right)\to 2KCl\left(s\right) + 3O_2\left(g\right)$

$2{\mathrm{KClO}}_3\left(s\right)⟶2\mathrm{KCl}\left(s\right)+3{\mathrm{O}}_2\left(g\right)$

Part (d) Step 1: Given information

We have been given four equations and we have to check which equation is balanced.

Part(d) Step 2: Explanation

To determine whether or not an equation is balanced, we apply the procedures below:

• Divide each molecule into its constituent atoms. Calculate the number of each type of atom in each molecule.
• Count the number of atoms of each kind on each side of the equation (for the reactants and the result).
• The element is balanced if the number of atoms on both sides of the equation equals one.
• If all of the elements are balanced, the equation is balanced.

We get what we want by following these steps.

$\mathrm{Mg}\left(s\right)+{\mathrm{N}}_2\left(g\right)⟶{\mathrm{Mg}}_3{ \mathrm{N}}_2\left(s\right)$

The reaction is not balanced.  

The balanced reaction is:

$3\mathrm{Mg}\left(s\right)+{\mathrm{N}}_2\left(g\right)⟶{\mathrm{Mg}}_3{ \mathrm{N}}_2\left(s\right)$