Arrange the following in order of property indicated for set:
`HF, HCl, HBr, HI` - decreasing bond enthalpy

Explanation

To arrange the compounds HF, HCl, HBr, and HI in order of decreasing bond enthalpy, we need to consider the strength of the bonds formed between hydrogen and the halogens (F, Cl, Br, I). The bond enthalpy is the amount of energy required to break a bond, and it is influenced by the electronegativity of the atoms involved.

### Step-by-Step Solution:

1. **Understand Bond Enthalpy**: Bond enthalpy is the energy required to break a bond between two atoms. A higher bond enthalpy indicates a stronger bond.

2. **Consider Electronegativity**: The bond strength is influenced by the electronegativity of the halogen atoms. The more electronegative the atom, the stronger the bond it forms with hydrogen. The electronegativity values for the halogens are as follows:
- Fluorine (F): Highest electronegativity
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