Which of the following chemicals is used for poisoning the specimens in herbarium technique?

Options

A. `Hg_(2)Cl_(2)`
B. `AgNO_(3)`
C. `HCl`
D. `HgCl_(2)`

Answer

To answer the question about which chemical is used for poisoning specimens in the herbarium technique, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Herbarium Technique**: The herbarium technique is a method used to preserve plant specimens for taxonomic studies. It involves drying and mounting the specimens on sheets of paper.

2. **Identify the Purpose of Chemicals in Herbarium**: In the herbarium technique, certain chemicals are used to prevent decay and preserve the specimens. One of the key roles of these chemicals is to act as a poisoning agent to kill any pests or microorganisms that could damage the specimens.

3. **Know the Common Chemicals Used**: The most commonly used chemical for this purpose is mercuric chloride (HgCl2). It is effective in preserving plant specimens and preventing decay.

4. **Evaluate the Given Options**: The options provided are:
- Ag2Cl2
- AgNO3
- HCl
- AgCl2
- HgCl2

5. **Select the Correct Chemical**: Among the options, mercuric chloride (HgCl2) is the correct answer. It is specifically mentioned as a 2% solution used in the herbarium technique.

6. **Conclusion**: Therefore, the chemical used for poisoning the specimens in the herbarium technique is **HgCl2 (mercuric chloride)**.

### Final Answer:
The correct answer is **HgCl2 (mercuric chloride)**.

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