Formula of peroxodisulphuric acid(Marshall"s acid) is

Options

A. `H_2SO_5`
B. `H_2S_2O_5`
C. `H_2S_2O_7`
D. `H_2S_2O_8`

Answer

To determine the formula of peroxodisulfuric acid (also known as Marshall's acid), we can follow these steps:

### Step 1: Understanding the Components
Peroxodisulfuric acid is a compound that contains sulfur and oxygen. The term "peroxo" indicates the presence of a peroxy linkage (–O–O–) in the structure.

### Step 2: Identifying the Structure
The structure of peroxodisulfuric acid consists of two sulfur atoms (S) and multiple oxygen atoms (O). The presence of the peroxy linkage suggests that there are additional oxygen atoms involved.

### Step 3: Writing the Chemical Formula
From the information provided, we can deduce that peroxodisulfuric acid has the following components:
- 2 sulfur atoms (S)
- 8 oxygen atoms (O)
- 2 hydrogen atoms (H)

Thus, the molecular formula can be constructed as:
\[ \text{H}_2\text{S}_2\text{O}_8 \]

### Step 4: Finalizing the Formula
The final formula for peroxodisulfuric acid, also known as Marshall's acid, is:
\[ \text{H}_2\text{S}_2\text{O}_8 \]

### Conclusion
The formula of peroxodisulfuric acid (Marshall's acid) is \( \text{H}_2\text{S}_2\text{O}_8 \).

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