Four acids `HA,HB,HC` and `HD` form salts with `NaOH` of `Ph` 7,8,9 and 10 respectively when each solution was `0.1M`, the strongest acid is `:`

Options

A. `HA`
B. `HB`
C. `HC`
D. `HD`

Explanation

To determine which of the four acids (HA, HB, HC, and HD) is the strongest based on the pH of their respective salts formed with NaOH, we can follow these steps:

### Step 1: Understand the relationship between pH and acidity
The pH scale measures the acidity or basicity of a solution. A lower pH indicates a higher concentration of hydrogen ions (H⁺), which corresponds to a stronger acid. Conversely, a higher pH indicates a weaker acid.

### Step 2: Analyze the given pH values
The pH values of the salts formed with NaOH are as follows:
- HA: pH 7
- HB: pH 8
- HC: pH 9
- HD: pH 10

### Step 3: Identify the trend in pH values
From the given pH values, we can see that:
- HA has the lowest pH (7)
- HB has a pH of 8
- HC has a pH of 9
- HD has the highest pH (10)

### Step 4: Relate pH to acid strength
Since HA has the lowest pH, it indicates that HA is the strongest acid among the four. This is because a strong acid will produce a salt that has a lower pH when neutralized with a strong base like NaOH.

### Step 5: Conclusion
Based on the analysis of the pH values, we conclude that the strongest acid is **HA**.

### Final Answer
The strongest acid is **HA**.

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