Perchloric acid is prepared by the action of connectrated sulphuric acid on

Options

A. `NaClO_(4)`
B. `KClO_(3)`
C. `Ca(ClO_(3))`
D. `Ba(ClO_(3))_(2)`

Explanation

To prepare perchloric acid (HClO4), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**: We need concentrated sulfuric acid (H2SO4) and a suitable chloride salt that contains the perchlorate ion (ClO4^-).

2. **Choose the Correct Chloride Salt**: The appropriate salt to react with concentrated sulfuric acid is sodium perchlorate (NaClO4).

3. **Write the Reaction**: When concentrated sulfuric acid reacts with sodium perchlorate, the following reaction occurs:
\[ 2 \text{NaClO}_4 + \text{H}_2\text{SO}_4 \rightarrow \text{Na}_2\text{SO}_4 + 2 \text{HClO}_4 \]

4. **Balance the Equation**: Ensure that the number of atoms for each element is equal on both sides of the equation. The equation above is balanced, with 2 sodium (Na), 2 chlorine (Cl), 4 oxygen (O) from perchlorate, and 1 sulfur (S) from sulfuric acid.

5. **Conclusion**: The product of this reaction is perchloric acid (HClO4) along with sodium sulfate (Na2SO4). Therefore, the correct answer to the question is that perchloric acid is prepared by the action of concentrated sulfuric acid on sodium perchlorate (NaClO4).

### Final Answer:
Perchloric acid is prepared by the action of concentrated sulfuric acid on sodium perchlorate (NaClO4).

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