Industrial name for `H_2 S_2 O_7` is

Options

A. Pyrosulphuric acid
B. Marshall's acid
C. Oleum
D. All of the above

Explanation

To find the industrial name for the compound \( H_2S_2O_7 \), we can follow these steps:

### Step 1: Identify the compound
The given chemical formula \( H_2S_2O_7 \) indicates that it contains hydrogen (H), sulfur (S), and oxygen (O).

### Step 2: Determine the structure
The compound \( H_2S_2O_7 \) can be recognized as a type of sulfuric acid. It is derived from the oxidation of sulfur compounds and contains two sulfur atoms.

### Step 3: Name the compound
The industrial name for \( H_2S_2O_7 \) is **Oleum** or **Pyrosulfuric Acid**. Oleum is often used in industrial processes, particularly in the production of sulfuric acid.

### Step 4: Confirm the name
To confirm, we can check that oleum is indeed a common name for \( H_2S_2O_7 \) in industrial contexts, and it is often used to describe concentrated sulfuric acid solutions that contain dissolved sulfur trioxide.

### Final Answer
The industrial name for \( H_2S_2O_7 \) is **Oleum** or **Pyrosulfuric Acid**.

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