Turnbull's blue and Prassian's blue respectively are
I. `Fe^(II)[Fe^(II)(CN)_(6)]^(2-)`
II.`Fe^(III)[Fe^(III)(CN)_(6)]` ,III.`Fe^(II)[Fe^(III)(CN)_(6)]^(Theta)` ,II.`Fe^(III)[Fe^(II)(CN)_(6)]^(Theta)`
IV

Options

A. I,III
B. I,III
C. III,IV
D. IV,III

Answer

To determine which compounds correspond to Turnbull's blue and Prussian blue, we can analyze the provided options based on their chemical compositions and oxidation states of iron.

### Step-by-Step Solution:

1. **Understanding Turnbull's Blue and Prussian Blue:**
- Turnbull's blue is a compound formed when a ferrous ion (Fe²⁺) reacts with ferricyanide (Fe³⁺[CN]₆³⁻).
- Prussian blue is formed when a ferric ion (Fe³⁺) reacts with ferrocyanide (Fe²⁺[CN]₆⁴⁻).

2. **Identifying the Chemical Formulas:**
- Turnbull's blue can be represented as Fe²⁺[Fe³⁺(CN)₆]²⁻.
- Prussian blue can be represented as Fe³⁺[Fe²⁺(CN)₆]⁴⁻.

3. **Analyzing the Given Options:**
- I. `Fe^(II)[Fe^(II)(CN)_(6)]^(2-)` - This does not match either compound.
- II. `Fe^(III)[Fe^(III)(CN)_(6)]` - This does not match either compound.
- III. `Fe^(II)[Fe^(III)(CN)_(6)]^(Theta)` - This matches Turnbull's blue.
- IV. `Fe^(III)[Fe^(II)(CN)_(6)]^(Theta)` - This matches Prussian blue.

4. **Conclusion:**
- Based on the analysis, Turnbull's blue corresponds to option III and Prussian blue corresponds to option IV.

### Final Answer:
- Turnbull's blue is represented by option III: `Fe^(II)[Fe^(III)(CN)_(6)]^(Theta)`.
- Prussian blue is represented by option IV: `Fe^(III)[Fe^(II)(CN)_(6)]^(Theta)`.