In which of the following S has highest oxidation state ?

Options

A. `Na_2S_4O_6`
B. `S_2Cl_2`
C. `S_8`
D. `H_2SO_4`

Answer

To determine which compound has sulfur in the highest oxidation state, we will analyze each option one by one.

### Step 1: Analyze Na2S4O6
1. Write the formula: Na2S4O6
2. Assign known oxidation states:
- Sodium (Na) = +1
- Oxygen (O) = -2
3. Let the oxidation state of sulfur (S) be \( x \).
4. The total charge of the molecule is 0 (neutral molecule).
5. Set up the equation based on the oxidation states:
\[ 2(+1) + 4x + 6(-2) = 0 \]
Simplifying gives:
\[ 2 + 4x - 12 = 0 \implies 4x - 10 = 0 \implies 4x = 10 \implies x = 2.5 \]
6. The average oxidation state of sulfur in Na2S4O6 is +2.5.

### Step 2: Analyze S2Cl2
1. Write the formula: S2Cl2
2. Assign known oxidation states:
- Chlorine (Cl) = -1
3. Let the oxidation state of sulfur be \( x \).
4. Set up the equation:
\[ 2x + 2(-1) = 0 \]
Simplifying gives:
\[ 2x - 2 = 0 \implies 2x = 2 \implies x = 1 \]
5. The oxidation state of sulfur in S2Cl2 is +1.

### Step 3: Analyze S8
1. Write the formula: S8
2. In its elemental form, the oxidation state of sulfur is 0.

### Step 4: Analyze H2SO4
1. Write the formula: H2SO4
2. Assign known oxidation states:
- Hydrogen (H) = +1
- Oxygen (O) = -2
3. Let the oxidation state of sulfur be \( x \).
4. Set up the equation:
\[ 2(+1) + x + 4(-2) = 0 \]
Simplifying gives:
\[ 2 + x - 8 = 0 \implies x - 6 = 0 \implies x = 6 \]
5. The oxidation state of sulfur in H2SO4 is +6.

### Conclusion
After analyzing all options:
- Na2S4O6: +2.5
- S2Cl2: +1
- S8: 0
- H2SO4: +6

The highest oxidation state of sulfur is in H2SO4, which is +6.

### Final Answer
The compound in which sulfur has the highest oxidation state is **H2SO4**.

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