Which of the following can be termed as mixed complex? .

Options

A. a.`K_(4)[Fe(CN)_(6)]`
B. b.`[Cu(NH_(3))_(4)]SO_(4)`
C. c.`[Co(NH_(3))_(4)NO_(2)CI]CI`
D. d.`K_(2)FeSO_(4)`

Answer

To determine which of the given options can be termed as a mixed complex, we need to understand what a mixed complex is. A mixed complex is a coordination compound that contains more than one type of ligand.

Let's analyze the options step by step:

### Step 1: Understand the definition of mixed complexes
- Mixed complexes are coordination compounds that contain multiple types of ligands.
- They are characterized by their high stability due to the presence of different ligands that can stabilize the metal center.

### Step 2: Analyze the options provided
1. **Option A**: Contains only one type of ligand (cyanide).
- This cannot be a mixed complex since it lacks multiple ligands.

2. **Option B**: Contains only one type of ligand (ammonium).
- Similar to Option A, this cannot be a mixed complex.

3. **Option C**: Contains three types of ligands (NH3, NO2, and Cl).
- This option has multiple ligands, making it a candidate for a mixed complex.

4. **Option D**: Is not a complex compound at all.
- This option cannot be a mixed complex since it is not a coordination compound.

### Step 3: Conclusion
- Based on the analysis, **Option C** is the only one that contains multiple types of ligands (NH3, NO2, and Cl) and can therefore be classified as a mixed complex.

### Final Answer
- The answer is **Option C**.

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