What is the oxidation state of CI in `HCIO_(4)` ?

Explanation

To find the oxidation state of chlorine (Cl) in the compound HClO₄ (perchloric acid), we can follow these steps:

### Step 1: Identify the oxidation states of other elements in the compound
- Hydrogen (H) typically has an oxidation state of +1.
- Oxygen (O) typically has an oxidation state of -2.

### Step 2: Write the equation based on the oxidation states
The formula for HClO₄ consists of:
- 1 hydrogen atom
- 1 chlorine atom
- 4 oxygen atoms

We can set up the equation based on the total oxidation states:
\[ \text{Total oxidation state} = 0 \]
This gives us:
\[ (+1) + (x) + 4(-2) = 0 \]
Where \(x\) is the oxidation state of chlorine.

### Step 3: Substitute the known values into the equation
Substituting the values we have:
\[ 1 + x - 8 = 0 \]

### Step 4: Solve for the oxidation state of chlorine
Now, simplify the equation:
\[ x - 7 = 0 \]
\[ x = +7 \]

### Conclusion
The oxidation state of chlorine in HClO₄ is +7.

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