White, odourless, bitter crystalline compound which are chemically diacetyl morphine is :-

Answer

**Step-by-Step Solution:**

1. **Identify the Chemical Name**: The question states that the compound is chemically known as diacetylmorphine.

2. **Recognize Common Names**: Diacetylmorphine is more commonly known as heroin.

3. **Describe Physical Properties**: Heroin is characterized as a white, odourless, and bitter crystalline compound.

4. **Source of the Compound**: Heroin is derived from the acetylation of morphine, which is a natural substance.

5. **Source Plant**: Morphine is extracted from the latex of the poppy plant, specifically from the species Papaver somniferum.

6. **Methods of Ingestion**: Heroin can be ingested through various methods, including snorting or injection.

7. **Function of the Compound**: Heroin acts as a depressant, meaning it slows down the body’s functions.

**Final Answer**: The white, odourless, bitter crystalline compound chemically known as diacetylmorphine is heroin.

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