Mn_{2}O_{7} is an acidic molecule so it can react with acid molecules stronger. Let us see what happens when H_{2}SO_{4} reacts with Mn_{2}O_{7}.

**In Mn _{2}O_{7}, the oxidation state of Mn is +7, so it is the most oxidizing agent and can undergo reduction and can oxidize other elements or molecules. The molecule is also known as manganese heptaoxide where the Mn-O-Mn bond is observed along with double-bonded oxygen.**

The reaction between Mn_{2}O_{7} and H_{2}SO_{4} does not require any kind of catalyst or temperature. Let us discuss the mechanism of the reaction between sulfuric acid and manganese, the reaction enthalpy, the type of reaction, product formation, etc in the following part of the article.

## 1. What is the product of H_{2}SO_{4} and Mn_{2}O_{7}?

**Manganese sulfate is formed as the major product when H _{2}SO_{4} and Mn_{2}O_{7} are reacted together along with water molecules.**

**H _{2}SO_{4} + Mn_{2}O_{7} = Mn_{2}(SO_{4})_{7} + H_{2}O**

## 2. What type of reaction is H_{2}SO_{4} + Mn_{2}O_{7}?

**The reaction between H**_{2}**SO**_{4}** + ****Mn _{2}O_{7}**

**is an example of a double displacement reaction along with redox and precipitation reactions. It is also a hydrolysis reaction.**

## 3. How to balance H_{2}SO_{4} + Mn_{2}O_{7}?

**We have to balance the equation, H_{2}SO_{4} + Mn_{2}O_{7} = Mn_{2}(SO_{4})_{7} + H_{2}O in the following way**:

**First, we label all the reactants and products by A, B, C, D, and E as there are only five different atoms obtained for this reaction and the reaction looks like this**:**A H**_{2}SO_{4}+ B Mn_{2}O_{7}= C Mn_{2}(SO_{4})_{7}+ D H_{2}O**Equating all the coefficients for all the same type of elements by rearranging them****After the rearrangement of all the coefficients of the same elements by their stoichiometric proportion we get, H = 2A = 2D, S = A = 7C, O = 4A = 7B = 28C = D, Mn = 2B = 2C****Using the Gaussian elimination and equating all the equations we get, A = 7, B = 1, C = 1, and D = 7****Now write the whole equation in the balanced form****The overall balanced equation will be,****7H**_{2}SO_{4}+ Mn_{2}O_{7}= Mn_{2}(SO_{4})_{7}+ 7H_{2}O

## 4. H_{2}SO_{4} + Mn_{2}O_{7} titration

**To estimate the quantity of manganese we can perform a titration between Mn _{2}O_{7} and H_{2}SO_{4}**

### Apparatus used

**We need a burette, conical flask, burette holder, volumetric flask, and beakers for this titration.**

### Titre and titrant

**H**_{2}**SO**_{4}** acts as a titrant which is taken in the burette and the molecule to be analyzed is ****Mn _{2}O_{7}**

**which is taken in a conical flask.**

### Indicator

**The whole titration is done in acidic pH as the concentration of H**_{2}**SO**_{4}** is high and for this reaction, ****Mn _{2}O_{7}**

**acts as a self-indicator because it is a colored solution and in different pH, it changes color.**

### Procedure

**The burette was filled with standardized H**_{2}**SO**_{4}** and ****Mn _{2}O_{7}**

**was taken in a conical flask along with the respective indicator. H**

_{2}**SO**

_{4}**is added dropwise to the conical flask and the flask was shaking constantly. After a certain time when the endpoint arrived,**

**Mn**

_{2}O_{7}**changes its color.**

We repeat the titration several times for better results and then we estimate manganese as well as sulfate quantity by the formula V_{1}S_{1 }= V_{2}S_{2}.

## 5. H_{2}SO_{4}+ Mn_{2}O_{7} net ionic equation

**The net ionic equation between H**_{2}**SO**_{4}** + ****Mn _{2}O_{7}**

**is as follows,**

**14H ^{+} + 7SO_{4}^{2-} + 2Mn^{2+} + 7O^{2-} = 2Mn^{2+} + 7SO_{4}^{2-} + H^{+} + OH^{–}**

**To derive the net ionic equation the following steps are required,**

**First H**_{2}SO_{4}will be ionized in proton and sulfate ions as it is a strong electrolyte**After that Mn**_{2}O_{7}also dissociates to Mn^{2+}ion and O^{2-}.**After that, the product Mn**_{2}(SO_{4})_{7}also dissociates to Mn^{2+}which is d^{5}stable configuration and corresponding SO_{4}^{2-}.**Water is also ionized to H**^{+}and OH^{-.}

## 6. H_{2}SO_{4}+ Mn_{2}O_{7} conjugate pairs

**H**_{2}**SO**_{4}** + ****Mn _{2}O_{7}**

**conjugate pairs will be the corresponding de-protonated and protonated form of that particular species which are listed below-**

**Conjugate pair of H**_{2}**SO**_{4}**= SO**_{4}^{2-}**Conjugate pair of OH**^{–}**= H**_{2}**O**

## 7. H_{2}SO_{4} and Mn_{2}O_{7} intermolecular forces

**The intermolecular force between H**_{2}**SO**_{4}** is an electrostatic, covalent force. For ****Mn _{2}O_{7},**

**it is ionic interaction, and peroxy linkage is present. In Mn**

_{2}(SO_{4})_{7}, strong ionic interactions are present along with dipole force and for water, H-bonding is present.Molecule | Actingforce |

H_{2}SO_{4} | Electrostatic, van der waal’s Dipole interaction |

Mn_{2}O_{7} | Ionic, peroxy linkage, and electrostatic |

Mn_{2}(SO_{4})_{7} | Coulombic force, strong ionic interaction, metallic bond |

H_{2}O | Covalent, H-bonding |

**Intermolecular Forces**

## 8. H_{2}SO_{4} + Mn_{2}O_{7} reaction enthalpy

**H**_{2}**SO**_{4}** + ****Mn _{2}O_{7}**

_{ }

**reaction enthalpy**

**is -5428 KJ/mol which can be obtained by the formula enthalpy of products – enthalpy of reactants, and here the change in enthalpy is negative.**

Molecule | Enthalpy(KJ/mol) |

Mn_{2}O_{7} | -726 |

H_{2}SO_{4} | -814 |

Mn_{2}(SO_{4})_{7} | -520 |

H_{2}O | -68 |

**Enthalpy of Reactants**

**and Products**

## 9. Is H_{2}SO_{4} + Mn_{2}O_{7} a buffer solution?

**The reaction between H**_{2}**SO**_{4}** +** **Mn _{2}O_{7 }**

**gives a buffer solution and they can control the pH of the solution.**

## 10. Is H_{2}SO_{4} + Mn_{2}O_{7} a complete reaction?

**The reaction between H _{2}SO_{4} + Mn_{2}O_{7 }is a complete reaction because it gives one complete product Mn_{2}(SO_{4})_{7 }along with the water molecule.**

**11. **Is H_{2}SO_{4} + Mn_{2}O_{7} an exothermic or endothermic reaction?

**The reaction H**_{2}**SO**_{4}** + ****Mn _{2}O_{7}**

**is exothermic in terms of thermodynamics first law. So, the reaction releases more energy and temperature to the surrounding so we have to be more cautious, where δH is always negative.**

## 12. Is H_{2}SO_{4} + Mn_{2}O_{7} a redox reaction?

**The reaction between H _{2}SO_{4} + Mn_{2}O_{7} is a **

**redox reaction**

**because in this reaction many elements get reduced and oxidized. Here, Mn gets reduced and S gets oxidized.**

## 13. Is H_{2}SO_{4} + Mn_{2}O_{7} a precipitation reaction

**The reaction H**_{2}**SO**_{4}** + ****Mn _{2}O_{7 }**

**is a precipitation reaction because Mn**

_{2}(SO_{4})_{7}gets precipitated in the solution and is not a soluble in the reaction mixture.## 14. Is H_{2}SO_{4} + Mn_{2}O_{7 }reversible or irreversible reaction?

**The reaction between H**_{2}**SO**_{4}**+ ****Mn _{2}O_{7}**

_{ }

**is irreversible because we get Mn**

_{2}(SO_{4})_{7 }**as a major product and the equilibrium of the reaction is shifted toward right hand side. Also, we can say the reaction goes to the forward direction only.**

## 15. Is H_{2}SO_{4} + Mn_{2}O_{7 }displacement reaction?

**The reaction between H _{2}SO_{4}+ Mn_{2}O_{7} is an example of a double displacement reaction because in the above reaction Mn displaced H^{+} in H_{2}SO_{4} and H^{+} also displaced Mn from Mn_{2}O_{7}.**

#### Conclusion

H_{2}SO_{4} and Mn_{2}O_{7} reaction mainly gives us Mn_{2}(SO_{4})_{7} along with water molecule. So, using this reaction we can produce manganese sulfate, and Mn_{2}O_{7} acts as strong oxidising agent here.