The oxidation number of sulphur in caro's acid is +x. What is value of x.

Answer

To find the oxidation number of sulfur in Caro's acid (peroxy monosulfuric acid), we can follow these steps:

### Step 1: Write the chemical formula of Caro's acid.
Caro's acid is known as peroxy monosulfuric acid, and its chemical formula is H₂SO₅.

### Step 2: Identify the oxidation states of other elements in the compound.
In H₂SO₅:
- Hydrogen (H) has an oxidation state of +1.
- Oxygen (O) typically has an oxidation state of -2, but in peroxides, it has an oxidation state of -1. In H₂SO₅, there are two types of oxygen: one as part of the peroxide bond (which will be -1) and the others as normal oxides (which will be -2).

### Step 3: Set up the equation for the sum of oxidation states.
Let the oxidation state of sulfur (S) be +x. The total oxidation state of the compound must equal 0 since it is neutral.

The formula can be broken down as follows:
- 2 hydrogen atoms contribute: 2(+1) = +2
- 1 sulfur atom contributes: +x
- 4 oxygen atoms contribute: 2(-1) for the peroxide and 2(-2) for the oxide = -2 - 4 = -6

### Step 4: Write the equation based on the total oxidation states.
The equation can be set up as:
\[ +2 + x - 6 = 0 \]

### Step 5: Solve for x.
Rearranging the equation gives:
\[ x - 4 = 0 \]
\[ x = +4 \]

### Conclusion
The oxidation number of sulfur in Caro's acid (H₂SO₅) is +6.

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