The correct order of reactivity of hydrogen halides with ethyl alcohol is

Options

A. `HCl gt HBr gt Hl gt HF`
B. `HI gt HBr gt HCl gt HF`
C. `HF gt HCl gt HBr gt HI`
D. `HF gt HBr gt HI gt HCl`

Answer

To determine the correct order of reactivity of hydrogen halides (HX) with ethyl alcohol (C2H5OH), we need to consider the bond dissociation energies of the hydrogen halides. Here’s a step-by-step solution:

### Step 1: Identify the Hydrogen Halides
The hydrogen halides we are considering are:
- HF (hydrogen fluoride)
- HCl (hydrogen chloride)
- HBr (hydrogen bromide)
- HI (hydrogen iodide)

### Step 2: Understand Bond Dissociation Energy
Bond dissociation energy is the energy required to break a bond. In this case, we are interested in the bond between hydrogen and the halogen (X) in HX. The lower the bond dissociation energy, the easier it is for the bond to break, which means higher reactivity.

### Step 3: Compare Bond Dissociation Energies
The bond dissociation energies of the hydrogen halides decrease in the following order:
- HF > HCl > HBr > HI

This means:
- HF has the highest bond dissociation energy and is the least reactive.
- HI has the lowest bond dissociation energy and is the most reactive.

### Step 4: Establish the Order of Reactivity
Since reactivity is inversely related to bond dissociation energy, we can establish the order of reactivity as follows:
- HI > HBr > HCl > HF

### Conclusion
The correct order of reactivity of hydrogen halides with ethyl alcohol is:
**HI > HBr > HCl > HF**