Question

• Give a balanced equation for Concentrated Hydrochloric acid and Potassium permanganate solution.

Answer 1

Step 1: Reacting to the given molecules:

• Powerful oxidising agents like Potassium permanganate oxidise Hydrochloric Acid to Chlorine.
• It reacts with Potassium permanganate to form Potassium Chloride, Manganese Chloride, Chlorine and water.

Step 2: Balancing the chemical equation

• The unbalanced chemical equation can be written as:
• $$\begin{gathered} \mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}{\mathbf{KMnO}}_{\mathbf{4}}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{HCl}\mathbf{}\mathbf{\left(}\mathbf{l}\mathbf{\right)}\mathbf{}\mathbf{\to }\mathbf{}\mathbf{KCl}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}{\mathbf{MnCl}}_{\mathbf{2}}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}{\mathbf{H}}_{\mathbf{2}}\mathbf{O}\mathbf{}\mathbf{\left(}\mathbf{l}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}{\mathbf{Cl}}_{\mathbf{2}}\mathbf{}\mathbf{\left(}\mathbf{g}\mathbf{\right)} \\ \mathbf{}\mathbf{Potassium}\mathbf{}\mathbf{}\mathbf{Hydrochloric}\mathbf{}\mathbf{Potassium}\mathbf{}\mathbf{Manganese} \\ \mathbf{permanganate}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{Acid}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{Chloride}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{Chloride} \end{gathered}$$
• The total number of atoms of each element on the reactant side and the product side must be compared.
• On the reactant side: $\mathbf{1}$ Potassium atom from ${\mathbf{KMnO}}_{\mathbf{4}}$, $\mathbf{1}$ Manganese atom from ${\mathbf{KMnO}}_{\mathbf{4}}$, $\mathbf{4}$ Oxygen atoms from ${\mathbf{KMnO}}_{\mathbf{4}}$, $\mathbf{1}$ an atom of Hydrogen from $\mathbf{HCl}$ and $\mathbf{1}$ Chlorine atom from $\mathbf{HCl}$
• On the product side: $\mathbf{1}$ Potassium atom from $\mathbf{KCl}$,$\mathbf{1}$ Manganese atom from ${\mathbf{MnCl}}_{\mathbf{2}}$, $\mathbf{5}$ Chlorine atoms from $\mathbf{KCl}$, ${\mathbf{MnCl}}_{\mathbf{2}}$ and ${\mathbf{Cl}}_{\mathbf{2}}$, $\mathbf{2}$ Hydrogen atoms from ${\mathbf{H}}_{\mathbf{2}}\mathbf{O}$ and $\mathbf{1}$ oxygen atom from ${\mathbf{H}}_{\mathbf{2}}\mathbf{O}$

Step 3: Balancing the reactant molecules by multiplying $\mathbf{2}$ by ${\mathbf{KMnO}}_{\mathbf{4}}$ in reactant side and 2 by $\mathbf{KCl}$ and ${\mathbf{MnCl}}_{\mathbf{2}}$in the product side.

• The chemical reaction is as follows:
• $$\begin{gathered} \mathbf{2}\mathbf{}{\mathbf{KMnO}}_{\mathbf{4}}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{HCl}\mathbf{}\mathbf{\left(}\mathbf{l}\mathbf{\right)}\mathbf{}\mathbf{\to }\mathbf{}\mathbf{2}\mathbf{}\mathbf{KCl}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{2}\mathbf{}{\mathbf{MnCl}}_{\mathbf{2}}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}{\mathbf{H}}_{\mathbf{2}}\mathbf{O}\mathbf{}\mathbf{\left(}\mathbf{l}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}{\mathbf{Cl}}_{\mathbf{2}}\mathbf{}\mathbf{\left(}\mathbf{g}\mathbf{\right)} \\ \mathbf{}\mathbf{Potassium}\mathbf{}\mathbf{}\mathbf{Hydrochloric}\mathbf{}\mathbf{Potassium}\mathbf{}\mathbf{Manganese} \\ \mathbf{permanganate}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{Acid}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{Chloride}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{Chloride} \end{gathered}$$
• On the reactant side: $\mathbf{2}$ Potassium atom from ${\mathbf{KMnO}}_{\mathbf{4}}$, $\mathbf{2}$ Manganese atom from ${\mathbf{KMnO}}_{\mathbf{4}}$, $\mathbf{8}$ Oxygen atoms from ${\mathbf{KMnO}}_{\mathbf{4}}$, $\mathbf{1}$ an atom of Hydrogen from $\mathbf{HCl}$ and $\mathbf{1}$ Chlorine atom from $\mathbf{HCl}$
• On the product side: $\mathbf{2}$ Potassium atom from $\mathbf{KCl}$,$\mathbf{2}$ Manganese atom from ${\mathbf{MnCl}}_{\mathbf{2}}$, $\mathbf{8}$ Chlorine atoms from $\mathbf{KCl}$, ${\mathbf{MnCl}}_{\mathbf{2}}$ and ${\mathbf{Cl}}_{\mathbf{2}}$, $\mathbf{2}$ Hydrogen atoms from ${\mathbf{H}}_{\mathbf{2}}\mathbf{O}$ and $\mathbf{1}$ oxygen atom from ${\mathbf{H}}_{\mathbf{2}}\mathbf{O}$

Step 4: Balancing the reactant molecules by multiplying $\mathbf{8}$ by $\mathbf{HCl}$ in reactant side and $\mathbf{4}$ by ${\mathbf{H}}_{\mathbf{2}}\mathbf{O}$in the product side.

1. The chemical reaction is as follows:
2. $$\begin{gathered} \mathbf{2}\mathbf{}{\mathbf{KMnO}}_{\mathbf{4}}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{8}\mathbf{}\mathbf{HCl}\mathbf{}\mathbf{\left(}\mathbf{l}\mathbf{\right)}\mathbf{}\mathbf{\to }\mathbf{2}\mathbf{}\mathbf{KCl}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{2}\mathbf{}{\mathbf{MnCl}}_{\mathbf{2}}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{4}\mathbf{}{\mathbf{H}}_{\mathbf{2}}\mathbf{O}\mathbf{}\mathbf{\left(}\mathbf{l}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}{\mathbf{Cl}}_{\mathbf{2}}\mathbf{}\mathbf{\left(}\mathbf{g}\mathbf{\right)} \\ \mathbf{}\mathbf{Potassium}\mathbf{}\mathbf{}\mathbf{Hydrochloric}\mathbf{}\mathbf{Potassium}\mathbf{}\mathbf{Manganese} \\ \mathbf{permanganate}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{Acid}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{Chloride}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{Chloride} \end{gathered}$$
3. After multiplication, we have an equal number of molecules on both sides of the reaction.
4. On the reactant side: $\mathbf{2}$ Potassium atom from ${\mathbf{KMnO}}_{\mathbf{4}}$, $\mathbf{2}$ Manganese atom from${\mathbf{KMnO}}_{\mathbf{4}}$, $\mathbf{8}$ Oxygen atoms from ${\mathbf{KMnO}}_{\mathbf{4}}$, $\mathbf{8}$ atom of Hydrogen from $\mathbf{HCl}$ and $\mathbf{8}$ Chlorine atom from $\mathbf{HCl}$
5. On the product side: $\mathbf{2}$ Potassium atom from $\mathbf{KCl}$,$\mathbf{2}$ Manganese atom from ${\mathbf{MnCl}}_{\mathbf{2}}$, $\mathbf{8}$ Chlorine atoms from $\mathbf{KCl}$, ${\mathbf{MnCl}}_{\mathbf{2}}$ and ${\mathbf{Cl}}_{\mathbf{2}}$, $\mathbf{8}$ Hydrogen atoms from ${\mathbf{H}}_{\mathbf{2}}\mathbf{O}$ and $\mathbf{4}$ oxygen atom from ${\mathbf{H}}_{\mathbf{2}}\mathbf{O}$

Step 5: Balanced chemical equation is as follows:

• The chemical reaction is as follows:
• $$\begin{gathered} \mathbf{2}\mathbf{}{\mathbf{KMnO}}_{\mathbf{4}}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{+}\mathbf{}\mathbf{8}\mathbf{}\mathbf{HCl}\mathbf{}\mathbf{\left(}\mathbf{l}\mathbf{\right)}\mathbf{}\mathbf{\to }\mathbf{2}\mathbf{}\mathbf{KCl}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{2}\mathbf{}{\mathbf{MnCl}}_{\mathbf{2}}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{4}\mathbf{}{\mathbf{H}}_{\mathbf{2}}\mathbf{O}\mathbf{}\mathbf{\left(}\mathbf{l}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}{\mathbf{Cl}}_{\mathbf{2}}\mathbf{}\mathbf{\left(}\mathbf{g}\mathbf{\right)} \\ \mathbf{}\mathbf{Potassium}\mathbf{}\mathbf{}\mathbf{Hydrochloric}\mathbf{}\mathbf{Potassium}\mathbf{}\mathbf{Manganese} \\ \mathbf{permanganate}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{Acid}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{Chloride}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{Chloride} \end{gathered}$$

Hence, the equation is balanced.