Ammonium cyanide, with the chemical formula NH4CN, is a highly toxic and extremely dangerous chemical compound. It is composed of ammonium ions (NH4+) and cyanide ions (CN-). Ammonium cyanide is a white, crystalline solid, but it is highly soluble in water.

Ammonium cyanide is one of the deadliest cyanide compounds, and its use and handling are strictly regulated due to its extreme toxicity. It is classified as a highly hazardous substance, and exposure to even small amounts can be fatal.

Some key points about ammonium cyanide include:

1. Toxicity: Ammonium cyanide is highly toxic when ingested, inhaled, or absorbed through the skin. It inhibits cellular respiration by interfering with the utilization of oxygen in the body.
2. Cyanide Poisoning: Exposure to ammonium cyanide can lead to cyanide poisoning, which is a life-threatening condition. Symptoms of cyanide poisoning can include headache, confusion, dizziness, rapid breathing, and loss of consciousness.
3. Laboratory Use: Historically, ammonium cyanide was used in some chemical synthesis processes and laboratory applications. However, due to its extreme toxicity and the availability of safer alternatives, its use has been largely discontinued.
4. Restrictions: The production, storage, and use of ammonium cyanide are highly regulated by various safety and environmental agencies due to its extreme toxicity and potential for harm.

Due to the extreme danger posed by ammonium cyanide, it should only be handled by trained professionals in well-equipped facilities with proper safety measures. It should never be used or handled outside of controlled laboratory or industrial settings.

If you encounter or suspect the presence of ammonium cyanide or any other toxic substances, it is crucial to seek immediate medical attention and notify relevant authorities for safe and proper disposal.