. The sum of the oxidation states of sulphur atoms in `H_2S_2O_5` is…….

Answer

To find the sum of the oxidation states of sulfur atoms in \( H_2S_2O_5 \), we can follow these steps:

### Step 1: Identify the Compound
The compound we are analyzing is \( H_2S_2O_5 \).

### Step 2: Assign Oxidation States
1. **Hydrogen (H)** has an oxidation state of +1. Since there are 2 hydrogen atoms, their total contribution is \( 2 \times (+1) = +2 \).
2. **Oxygen (O)** typically has an oxidation state of -2. In \( H_2S_2O_5 \), there are 5 oxygen atoms, so their total contribution is \( 5 \times (-2) = -10 \).

### Step 3: Set Up the Equation
Let the oxidation state of sulfur (S) be \( x \). Since there are 2 sulfur atoms in the compound, their total contribution will be \( 2x \).

The overall charge of the molecule is neutral (0), so we can set up the following equation:

\[ 2x + 2 + (-10) = 0 \]

### Step 4: Solve for \( x \)
Now, simplify the equation:

\[ 2x - 8 = 0 \]

Adding 8 to both sides gives:

\[ 2x = 8 \]

Dividing both sides by 2:

\[ x = 4 \]

### Step 5: Calculate the Total Oxidation State
Since there are 2 sulfur atoms, the total oxidation state for both sulfur atoms is:

\[ 2x = 2 \times 4 = 8 \]

### Conclusion
The sum of the oxidation states of sulfur atoms in \( H_2S_2O_5 \) is **8**.

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