The final product obtained for the following reaction is:
`KMnO_(4)("excess") +H_(2)SO_(4)("concentrated and cold") to`

Options

A. `Mn_(2)O_(7)`
B. `MnO`
C. `Mn_(3)O_(4)`
D. `MnO_(3)^(+)`

Explanation

To determine the final product obtained from the reaction of KMnO4 (potassium permanganate) with concentrated and cold H2SO4 (sulfuric acid), we can follow these steps:

### Step 1: Write the initial reaction
When KMnO4 is treated with concentrated and cold H2SO4, the reaction can be represented as:
\[ \text{KMnO}_4 + \text{H}_2\text{SO}_4 \rightarrow \text{KHSO}_4 + \text{MnO}_2 + \text{H}_2\text{O} \]
However, since we have excess KMnO4, we need to consider the complete reaction.

### Step 2: Balance the reaction
To balance the reaction, we need to account for the number of moles of each reactant and product. The balanced equation is:
\[ 2 \text{KMnO}_4 + 3 \text{H}_2\text{SO}_4 \rightarrow 2 \text{KHSO}_4 + \text{Mn}_2\text{O}_7 + 2 \text{H}_2\text{O} \]
Here, MnO3SO4 is formed, which is unstable and decomposes.

### Step 3: Identify the decomposition product
The MnO3SO4 decomposes in the presence of water (which is already present in the reaction) to form:
\[ \text{Mn}_2\text{O}_7 + \text{H}_2\text{SO}_4 \]
Mn2O7 is a green oily liquid that is known to be highly explosive.

### Step 4: Final product
The final product of the reaction is thus:
\[ \text{Mn}_2\text{O}_7 \]
This is the product we are looking for.

### Conclusion
The final product obtained from the reaction of KMnO4 with concentrated and cold H2SO4 is Mn2O7.

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