Which of the manganese oxides is the most acidic from the given options ?

Options

A. `Mn_2O_3`
B. `MnO`
C. `MnO_2`
D. `Mn_2O_7`

Answer

To determine which manganese oxide is the most acidic, we need to analyze the oxidation states of manganese (Mn) in the given oxides. The acidic nature of oxides generally increases with the oxidation state of the central metal. Here’s a step-by-step solution:

### Step 1: Identify the manganese oxides
The manganese oxides we need to analyze are:
- MnO
- MnO2
- Mn2O3
- Mn2O7

### Step 2: Calculate the oxidation state of Mn in each oxide

#### For MnO:
- Let the oxidation state of Mn be \( x \).
- The oxidation state of oxygen (O) is \(-2\).
- The equation becomes:
\[ x - 2 = 0 \implies x = +2 \]

#### For MnO2:
- Let the oxidation state of Mn be \( x \).
- The equation becomes:
\[ x - 4 = 0 \implies x = +4 \]

#### For Mn2O3:
- Let the oxidation state of Mn be \( x \).
- The equation becomes:
\[ 2x - 6 = 0 \implies 2x = 6 \implies x = +3 \]

#### For Mn2O7:
- Let the oxidation state of Mn be \( x \).
- The equation becomes:
\[ 2x - 14 = 0 \implies 2x = 14 \implies x = +7 \]

### Step 3: Compare the oxidation states
Now we have the oxidation states of Mn in each oxide:
- MnO: +2
- MnO2: +4
- Mn2O3: +3
- Mn2O7: +7

### Step 4: Determine the most acidic oxide
The acidic nature increases with the increase in oxidation state. Therefore, the oxide with the highest oxidation state of Mn, which is Mn2O7 (+7), will be the most acidic.

### Conclusion
The most acidic manganese oxide from the given options is **Mn2O7**.