The following acids have been arranged in order of decreasing acid strength. Identify the correct order.
ClOH (I) , BrOH (II) , IOH(III)

Options

A. (A) l gt ll gt lll
B. (B) ll gt l gt lll
C. (C) lll gt ll gt l
D. (D) l gt lll gt ll

Answer

To determine the order of decreasing acid strength for the acids ClOH (hypochlorous acid), BrOH (hypobromous acid), and IOH (hypoiodous acid), we need to consider the electronegativity of the halogens involved, as well as how easily these acids can donate a proton (H⁺).

### Step-by-Step Solution:

1. **Understanding Acid Strength**: Acid strength is often determined by the ability of the acid to donate a proton (H⁺). The easier it is for an acid to lose a proton, the stronger the acid.

2. **Electronegativity of Halogens**: The strength of these acids is influenced by the electronegativity of the halogen atom bonded to the hydroxyl group (OH). The more electronegative the halogen, the stronger the acid tends to be because it can stabilize the negative charge that results when the proton is lost.

3. **Electronegativity Values**:
- Chlorine (Cl) has the highest electronegativity among the three halogens.
- Bromine (Br) has a lower electronegativity than chlorine.
- Iodine (I) has the lowest electronegativity of the three.

The order of electronegativity is: Cl > Br > I.

4. **Comparing Acids**:
- **ClOH (Hypochlorous Acid)**: Being attached to chlorine, it has the highest electronegativity, making it the strongest acid among the three.
- **BrOH (Hypobromous Acid)**: With bromine, it is less electronegative than chlorine, thus it is a weaker acid than ClOH but stronger than IOH.
- **IOH (Hypoiodous Acid)**: Iodine is the least electronegative, making this acid the weakest among the three.

5. **Final Order**: Based on the electronegativity and the ability to donate protons, the order of decreasing acid strength is:
- ClOH > BrOH > IOH

### Conclusion:
The correct order of decreasing acid strength is:
**ClOH > BrOH > IOH**