Four species are listed below:
(`i`) `HCO_(3)^(-)`
(`ii`) `H_(3)O^(+)`
(`iii`) `HSO_(4)^(-)`
(`iv`) `HSO_(3)F`
Which one of the following is the correct sequence of their acid strength?

Options

A. `ivltiiltiiilti`
B. `iiltiiiltiltiv`
C. `iltiiiltiiltiv`
D. `iiiltiltivltii`

Explanation

To determine the correct sequence of acid strength for the given species, we will analyze their acid dissociation constants (pKa values) and compare them. The lower the pKa value, the stronger the acid.

### Step-by-Step Solution:

1. **Identify the Species and Their pKa Values**:
- `HCO₃⁻` (Bicarbonate ion): pKa ≈ 10.25
- `H₃O⁺` (Hydronium ion): pKa ≈ 1.74
- `HSO₄⁻` (Hydrogen sulfate ion): pKa ≈ 1.92
- `HSO₃F` (Bisulfite fluoride): This is known to be a super acid, which means it has a very low pKa value (typically much lower than 1).

2. **Compare the pKa Values**:
- `H₃O⁺` has the lowest pKa (1.74), indicating it is the strongest acid.
- `HSO₄⁻` has the next lowest pKa (1.92), making it the second strongest acid.
- `HSO₃F` is a super acid, which means it is stronger than both `H₃O⁺` and `HSO₄⁻`, thus it comes first in the sequence.
- `HCO₃⁻` has the highest pKa (10.25), indicating it is the weakest acid among the four.

3. **Establish the Sequence of Acid Strength**:
- Based on the pKa values, the order of acid strength from strongest to weakest is:
- `HSO₃F` > `H₃O⁺` > `HSO₄⁻` > `HCO₃⁻`

4. **Final Answer**:
- The correct sequence of acid strength is:
- `HSO₃F` > `H₃O⁺` > `HSO₄⁻` > `HCO₃⁻`