The `EN's` of `F, CI` Br and I are 4.0 ,3.0, 2.8 and 2.5 respectively The hybrogen halide with a highest percentage of ionic character is .

Options

A. `HI`
B. `HBr`
C. `HCI`
D. `HF`

Explanation

To determine which hydrogen halide has the highest percentage of ionic character, we can follow these steps:

### Step 1: Understand Electronegativity
Electronegativity (EN) is a measure of an atom's ability to attract and hold onto electrons. The greater the difference in electronegativity between two bonded atoms, the more ionic character the bond will have.

### Step 2: List the Electronegativity Values
From the question, we have the following electronegativity values:
- Fluorine (F): 4.0
- Chlorine (Cl): 3.0
- Bromine (Br): 2.8
- Iodine (I): 2.5

### Step 3: Calculate the Electronegativity Differences
Next, we will calculate the electronegativity differences for each hydrogen halide:
- For HF: |4.0 - 2.1| = 1.9
- For HCl: |3.0 - 2.1| = 0.9
- For HBr: |2.8 - 2.1| = 0.7
- For HI: |2.5 - 2.1| = 0.4

### Step 4: Determine the Ionic Character
The percentage of ionic character is directly proportional to the electronegativity difference. Therefore, the greater the difference, the higher the ionic character.

### Step 5: Compare the Differences
Now we can compare the electronegativity differences:
- HF: 1.9
- HCl: 0.9
- HBr: 0.7
- HI: 0.4

### Step 6: Conclusion
Since HF has the highest electronegativity difference (1.9), it will have the highest percentage of ionic character among the hydrogen halides.

### Final Answer
The hydrogen halide with the highest percentage of ionic character is **HF (Hydrogen Fluoride)**.

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