Iodine is not oxidized to iodic acid/iodicanhydride by:

Options

A. conc. `HNO_(3)`
B. conc. `H_(2)SO_(4)`
C. Excess `Cl_(2)` water
D. conc. `H_(3)PO_(4)`

Explanation

To determine which reagent does not oxidize iodine (I2) to iodic acid (HIO3) or iodic anhydride, we will analyze the oxidation reactions of iodine with the given reagents. The oxidation of iodine involves the loss of electrons, which can be represented by an increase in its oxidation state.

### Step-by-Step Solution:

1. **Understanding Oxidation**:
- Oxidation is defined as the loss of electrons. In this case, iodine (I2) in its elemental form has an oxidation state of 0. When it is oxidized to iodic acid (HIO3), its oxidation state increases to +5.

2. **Analyzing Each Reagent**:
- **Reagent A: Concentrated HNO3 (Nitric Acid)**:
- When I2 reacts with concentrated HNO3, it is oxidized to iodic acid (HIO3). This is a known reaction where nitric acid acts as a strong oxidizing agent.
- **Reagent B: Concentrated H2SO4 (Sulfuric Acid)**:
- Similarly, when I2 is treated with concentrated H2SO4, it is also oxidized to iodic acid (HIO3). Sulfuric acid is another strong oxidizing agent.
- **Reagent C: Excess Cl2 in Water**:
- Chlorine (Cl2) in water is a powerful oxidizing agent and can oxidize iodine to iodic acid (HIO3) as well.
- **Reagent D: Concentrated H3PO4 (Phosphoric Acid)**:
- Phosphoric acid (H3PO4) does not have strong oxidizing properties. Therefore, when I2 is treated with concentrated H3PO4, there is no oxidation of iodine to iodic acid.

3. **Conclusion**:
- The reagent that does not oxidize iodine to iodic acid or iodic anhydride is **Concentrated H3PO4 (Phosphoric Acid)**.

### Final Answer:
Iodine is not oxidized to iodic acid/iodic anhydride by **Concentrated H3PO4 (Phosphoric Acid)**.

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