Find incorrect statement about manganate and permanganate ions

Options

A. both manganate & permanganate ions are paramagnetic
B. manganate ion is green in color while permanganate ion is purple in color
C. both manganate & permanganete ions have tetrahedral shape
D. in manganate & permanganate ions Mn form `ppi-dpi` bond eith oxygen

Answer

To solve the problem of identifying the incorrect statement about manganate (MnO4^2-) and permanganate (MnO4^-), we will analyze each statement step by step.

### Step 1: Understand the ions
- **Manganate ion (MnO4^2-)**: Manganese in this ion has an oxidation state of +6.
- **Permanganate ion (MnO4^-)**: Manganese in this ion has an oxidation state of +7.

### Step 2: Determine the electronic configurations
- Manganese (Mn) has the electronic configuration of [Ar] 3d^5 4s^2.
- In the manganate ion (MnO4^2-), Mn is in the +6 oxidation state, leading to the configuration of 3d^5 (one 4s electron is removed).
- In the permanganate ion (MnO4^-), Mn is in the +7 oxidation state, leading to the configuration of 3d^0 (both 4s electrons are removed).

### Step 3: Check for unpaired electrons
- **Manganate ion (MnO4^2-)**: Has 1 unpaired electron (3d^5).
- **Permanganate ion (MnO4^-)**: Has no unpaired electrons (3d^0).

### Step 4: Analyze the magnetic properties
- **Manganate ion**: Paramagnetic due to the presence of one unpaired electron.
- **Permanganate ion**: Diamagnetic due to the absence of unpaired electrons.

### Step 5: Evaluate the statements
1. **Statement 1**: "Both manganate and permanganate ions are paramagnetic."
- **Analysis**: This statement is **incorrect** because manganate is paramagnetic while permanganate is diamagnetic.

2. **Statement 2**: "Manganate ion is blue in color while the permanganate ion is purple in color."
- **Analysis**: This statement is **correct**. Manganate ions are typically green, but they can appear blue in certain conditions, while permanganate ions are purple.

3. **Statement 3**: "Both manganate and permanganate ions have tetrahedral shape."
- **Analysis**: This statement is **incorrect**. Manganate has a tetrahedral shape, but permanganate has a tetrahedral shape as well.

4. **Statement 4**: "In manganate and permanganate, manganese forms p-π-d-π bonds with oxygen."
- **Analysis**: This statement is **correct**. The bonding involves p-π-d-π interactions.

### Conclusion
The incorrect statement is **Statement 1**: "Both manganate and permanganate ions are paramagnetic."