Manganese Heptoxide
What is it? And the explanation behind why it is so reactive
What is Manganese Heptoxide?
1
- It was Discovered in 1860
- Has the formula Mn2O7 and has 6 DOUBLE BONDS
- It also has a charge of -14
- Non-polar
- Liquid at room temperature, and has a melting point at 5.7°C
- Is a very dangerous oxidizer and reacts with nearly every organic compound
- Possible through hybridization
What causes a Chemical Reaction?
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- A reaction is caused by one or more reactants undergoing a chemical change
- This can be explained using collision theory
- Atoms must collide at the right orientation and energy for break and from new bonds
- This is called activation energy
- There are six factors that affect the rate of a reaction
- Increasing temperature speeds up atoms and allows more to reach activation energy
Tempe--rature
Pressure
- Works for gases, brings atoms closer together, allowing for more collisions
Conce-ntration
- Works for solutions, having a larger abundance of an atom increase the amount of collisions
- Electronegativities affect the activation energy (Higher electronegativity, lower activation energy), increasing the rate of reaction
Nature of Reactants
Catalyst
- Catalysts lower activation energy of a reaction
- Increasing surface area allows for more collisions to occur around the atoms
Surface Area
Fun Fact: Hypergolic reactions are the same reactions performed to ignite rocket ships in and out of oxygen deprived environments
What Reaction Does Manganese Heptoxide undergo?
3
- It undergoes an redox or oxidation reaction
- It can also undergo autoxidation, oxidizing with itself
- The true name is hypergolic reaction
- Oxidation works by breaking bonds and giving electrons to the receiving element/compound
- Ex. Fruits browning, metal rusting, fluorine
Why is Manganese Heptoxide so Reactive?
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- Having 6 double bonds and a charge of -14 makes it fourteen unstable
- Lots of energy within in double bonds
- Has seven oxygen, which is a very reactive element
- When a bond is broken to oxidize, which will always happen, the atom must constantly re-hybridize to stay stable
- But in the process after each bond is broken, more energy is produced
- Reactions have an upward of 57°C.
Fun Fact: The ozone produced can undergo a combustion reactions immediately after its is produced, if the energy produced is high enough
Reaction
- An oxidation reaction with Mn2O7 creates the products of MnO2 + O2 + O3 (ozone).
- It can then undergo a combustion reaction (depending on other reagent in sequence
- Creating the products CO2 and H2O
How is Manganese Heptoxide Formed?
- Is created at room temperature (22°C)
- Is an exothermic reaction, producing energy when formed
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2KMnO4(s) + H2SO4 (aq) -> Mn2O7 (aq) + H2O (l) + 2KHSO4 (aq)
Activation energy would be 22°C
Mn2O7 (aq) + H2O (l) + 2KHSO4 (aq)
Enthalpy Diagram
Would be a negative value because this is an exothermic reaction
Are there any Applications of this Compound?
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- No, none that aren't done better by other compounds
- Best thing I could think of:
- Oxidizing agent for rocket engines
- Entertaining videos for bored grade 12 chem students to watch
- With it being so volatile, it is hard to find anything useful