Acidified `K_(2)Cr_(2)O_(7)` on reaction with hydrogen peroxide give deep blue solution due to formation of

Options

A. `Cr_(2)(SO_(4))_(3)`
B. `CrO_(5)`
C. `CrO_(4)^(2-)`
D. `Cr_(2)O_(3)`

Answer

To answer the question regarding the reaction of acidified potassium dichromate (K₂Cr₂O₇) with hydrogen peroxide (H₂O₂) that results in a deep blue solution, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**: The reactants in this reaction are acidified potassium dichromate (K₂Cr₂O₇) and hydrogen peroxide (H₂O₂). The acidification is typically done using sulfuric acid (H₂SO₄).

2. **Write the Reaction**: The reaction can be represented as follows:
\[ K_2Cr_2O_7 + H_2O_2 + H_2SO_4 \rightarrow CrO_5 + K_2SO_4 + H_2O \]
Here, potassium dichromate reacts with hydrogen peroxide in the presence of sulfuric acid.

3. **Identify the Product**: The product of interest is chromium pentoxide (CrO₅), which is responsible for the deep blue color of the solution.

4. **Balancing the Reaction**: To ensure the reaction is balanced, we can write the balanced equation as:
\[ K_2Cr_2O_7 + 4 H_2O_2 + 2 H_2SO_4 \rightarrow 2 CrO_5 + K_2SO_4 + 5 H_2O \]
This shows that 1 mole of potassium dichromate reacts with 4 moles of hydrogen peroxide and 2 moles of sulfuric acid to produce 2 moles of chromium pentoxide, potassium sulfate, and water.

5. **Conclusion**: The deep blue color observed in the solution is due to the formation of chromium pentoxide (CrO₅).

### Final Answer:
The deep blue solution formed when acidified K₂Cr₂O₇ reacts with hydrogen peroxide is due to the formation of **chromium pentoxide (CrO₅)**.