Acidic oxide is formed by the metal and oxidation state of the metal in the oxide

Options

A. `Mn, +6`
B. `Mn, +7`
C. `Cr, +3`
D. `Cr, +7`

Answer

To solve the question regarding the acidic oxide formed by the metal and the oxidation state of the metal in the oxide, we can follow these steps:

### Step 1: Identify the Metals and Their Oxidation States
We are given two metals: Manganese (Mn) and Chromium (Cr). The oxidation states mentioned are:
- Manganese: +6 and +7
- Chromium: +3 and +6

### Step 2: Determine the Oxides Formed
Next, we need to identify the oxides that these metals form at the specified oxidation states:
- Manganese:
- MnO3 (Manganese in +6 oxidation state)
- Mn2O7 (Manganese in +7 oxidation state)
- Chromium:
- Cr2O3 (Chromium in +3 oxidation state)
- CrO3 (Chromium in +6 oxidation state)

### Step 3: Analyze the Acidic Nature of the Oxides
Acidic oxides are generally formed by metals in higher oxidation states. Therefore, we need to analyze the acidic nature of the oxides formed:
- MnO3 and Mn2O7 are acidic oxides. Mn2O7, with Mn in +7 oxidation state, is more acidic than MnO3.
- CrO3 is also an acidic oxide, with Cr in +6 oxidation state, which is known to be very acidic. Cr2O3 is less acidic.

### Step 4: Compare the Acidic Nature
Now, we compare the acidic nature of the oxides:
- Mn2O7 (Mn in +7) is more acidic than MnO3 (Mn in +6).
- CrO3 (Cr in +6) is more acidic than Cr2O3 (Cr in +3).

### Step 5: Conclusion
Among the given oxidation states, Mn in +7 oxidation state (Mn2O7) is the most acidic oxide. Therefore, the answer to the question is that the acidic oxide is formed by manganese in the +7 oxidation state.

### Final Answer
The acidic oxide is Mn2O7, and the oxidation state of manganese in this oxide is +7.

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