Preparatory Method of Hydrazoic Acid
Hydrazoic acid, also known as hydrogen azide, is a colorless, volatile, and explosive liquid with the chemical formula HN3. It is commonly used in the synthesis of various compounds and as a reagent in organic chemistry. Here is a detailed explanation of the preparatory method of hydrazoic acid:

1. Reacting Sodium Azide with Sulfuric Acid:
- The most common method for preparing hydrazoic acid is by reacting sodium azide (NaN3) with sulfuric acid (H2SO4).
- The reaction takes place in a two-step process, where sodium azide first reacts with sulfuric acid to form hydrazoic acid, along with the formation of sodium sulfate and water as byproducts.

2. Distillation of Hydrazoic Acid:
- Once the reaction is complete, the resultant mixture is distilled to separate the hydrazoic acid from the byproducts.
- Hydrazoic acid has a boiling point of around 37 °C, which allows for easy separation through distillation.

3. Purification of Hydrazoic Acid:
- The distilled hydrazoic acid is then purified to remove any impurities and ensure its high quality and purity.
- Various purification techniques such as fractional distillation or recrystallization can be employed for this purpose.

4. Storage and Handling:
- Due to its explosive nature, hydrazoic acid must be stored and handled with extreme caution.
- It should be kept in a cool, dry place away from heat, sparks, or open flames to prevent accidental explosions.
By following these steps, hydrazoic acid can be successfully prepared in the laboratory for use in various chemical reactions and applications.