Which of the following has highest molar conductivity

Options

A. Diaminedichloroplatinum (II)
B. Tetraaminedichlorocobalt (III) chloride
C. Potassium hexacyanoferrate (II)
D. Hexaaquochromium (III) bromide

Explanation

To determine which compound has the highest molar conductivity, we need to analyze the dissociation of each compound into ions. Molar conductivity is directly proportional to the number of ions produced when an electrolyte dissolves in solution. Here’s the step-by-step solution:

### Step 1: Understand Molar Conductivity
Molar conductivity (Λ) is defined as the conductivity (κ) of an electrolyte solution divided by its molarity (C). It can be expressed mathematically as:
\[ Λ = \frac{1000 \cdot κ}{C} \]
This means that the more ions produced by the dissociation of the electrolyte, the higher the molar conductivity.

### Step 2: Analyze Each Compound
1. **Diamine Dichloroplatinum (II)**:
- Structure: [Pt(NH3)2Cl2]
- Dissociation: This complex does not dissociate into multiple ions; it remains as one entity.
- Number of ions produced: 1 ion

2. **Tetramine Dichlorocobalt (II) Chloride**:
- Structure: [Co(NH3)4Cl2]Cl
- Dissociation: This complex can dissociate into 3 ions (1 Co complex + 2 Cl⁻).
- Number of ions produced: 3 ions

3. **Potassium Hexacyanoferrate (II)**:
- Structure: K4[Fe(CN)6]
- Dissociation: This compound dissociates into 5 ions (4 K⁺ + 1 [Fe(CN)6]⁴⁻).
- Number of ions produced: 5 ions

4. **Hexa Aqua Chromium (III) Bromide**:
- Structure: [Cr(H2O)6]Br3
- Dissociation: This complex dissociates into 4 ions (1 [Cr(H2O)6]³⁺ + 3 Br⁻).
- Number of ions produced: 4 ions

### Step 3: Compare the Number of Ions
- Diamine Dichloroplatinum (II): 1 ion
- Tetramine Dichlorocobalt (II) Chloride: 3 ions
- Potassium Hexacyanoferrate (II): 5 ions
- Hexa Aqua Chromium (III) Bromide: 4 ions

### Step 4: Conclusion
Since potassium hexacyanoferrate produces the maximum number of ions (5 ions), it will have the highest molar conductivity.

**Final Answer: Potassium Hexacyanoferrate has the highest molar conductivity.**