_____is known as king of chemicals.

Answer

**Step-by-Step Solution:**

1. **Identify the Subject of the Question:**
The question asks for a substance that is referred to as the "King of Chemicals."

2. **Recall the Relevant Information:**
From chemistry, we know that sulfuric acid (H₂SO₄) is commonly referred to as the "King of Chemicals."

3. **Explain the Reasons for this Title:**
- **Strong Acid:** Sulfuric acid is classified as a strong acid, meaning it completely dissociates in water, making it highly effective in chemical reactions.
- **Highly Corrosive:** It is known for its ability to corrode materials, which makes it dangerous and powerful in various applications.
- **Reactivity:** Sulfuric acid is more reactive than many other acids, allowing it to participate in a wide range of chemical reactions.
- **Ability to Dissolve Other Acids:** It can dissolve other acids, showcasing its strength and versatility.
- **Wide Range of Applications:** Sulfuric acid is used in numerous fields, including:
- Laboratories for various chemical reactions and experiments.
- Storage batteries, particularly in lead-acid batteries.
- Production of detergents and cleaning agents.
- Synthesis of many drugs and pharmaceuticals.

4. **Conclude the Answer:**
Based on the information gathered, the answer to the question is: **Sulfuric acid (H₂SO₄)** is known as the "King of Chemicals."

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