8 Facts About Nitrogen Triiodide

Ni3 cover

Chemistry is a fascinating subject, it deals with the chemical processes and their effects. Though the equations of chemical reactions and all are not fun whatsoever, the lab testing is quite interesting. Mixing and combing various liquids and solids give us a sense of being a scientist, but we’d have no idea what we are doing and sometimes things explode while we play the scientist. However, there are some compounds that are so explosive that they don’t even require a special treatment to detonate, a simple touch of a finger is enough to set them off, so what is this compound?

Nitrogen Triiodide

Nitrogen Triiodide is a contact explosive, meaning it will explode on contact. There are other contact explosives as well, like Nitro Glycerin where it is set off by hard contact say smashing a hammer against it but as for this explosive, it triggers with the slightest touch. In this three iodine atoms are stuck to a nitrogen atom. Its molecular formula is NI3.

Nitrogen Iodide 2D

2D molecular structure of Nitrogen Triiodide.

Facts about Nitrogen Triiodide

1. Nitrogen abundance: It is one of the most abundant elements in our environment and it is even present within us, as about 78% of the atmosphere consists of nitrogen and it plays a vital role in our DNA. It is also present in soil and water in the form of nitrates. Nitrogen is a trivalent atom, meaning, it falls in the category of other elements that prefer to make bonds with three other atoms.

2. Beautiful Iodine: Where nitrogen is pretty much everywhere, iodine isn’t as abundant. Also, it exists in a semi-lustrous and non-metallic solid state which under average conditions is stable. But once the temperature rises to 114°C it releases mesmerizing violet vapors which are considered prettiest throughout the periodic table. Even though they are beautiful to look at, they are harmful to us. This is the reason why nitrogen triiodide releases violet shade smoke upon exploding.

Iodine vapor

Iodine crystals releasing the violet vapors.

3. Non-Organic: As you can imagine, a substance with such instability doesn’t exist naturally. It is a synthesized compound and it is made by the reaction of iodine with ammonia, which is nitrogen and three hydrogen atoms and due to its unstable structure and non-organic nature, it is difficult to study as well. Because as soon as it is touched it is detonated.

4. Stressed Structure: Nitrogen being a trivalent element forms three bonds with iodine and once that happens it becomes unstable. As the nitrogen molecule is fairly small compared to iodine molecules, and the way nitrogen’s electrons are arranged all the three bonds exist on one side. This results in iodine molecules pushing onto each other as they don’t have enough room and being squeezed together they repel on each other and this results in a steric strain. This creates a really unstable environment for this compound resulting in the instant explosion as soon as it comes in contact with something.

5. Wet Stability: During the process of its creation it is wet and remarkably, being wet it is stable. Though it can still explode given the right conditions but compared to the dried state it is much stable and its appearance is not much different from carbon powder.

Wet Ni3

Wet phase in the production of Nitrogen Triiodide.

6. It’s Flashy: Not flashy in a sense of diamond or metals, but once it is about to explode just a millisecond before exploding, the detonation sparks the nitrogen triiodide and it appears like a shining crystal. Though it is impossible to see that with the naked eye, thanks to slow-motion camera technology we were able to find this property. According to scientists, it happens due to the excessive release of energy in such a tiny space but it is not an accepted explanation.

7. Useless: As much fun as it is to experiment with this highly reactive compound, it has no use commercially. Granted it is used in high schools year after year to demonstrate the change in entropy and the reactive nature of various materials, unfortunately, when it comes to having a practical use, there is none.

8. Easy to make: Even though it has no use in real life, it is fairly straightforward to produce and one can even make this explosive compound at home. All you need for this is ammonia, iodine crystals, and a plastic container, the reason why glass containers are not used in the experiment is because of the risk if they explode. Simply pour ammonia into the container and add iodine crystals into it and let it stay submerged for up to 10 minutes, then carefully scoop out the ammonia crystals and dry them and that’s all to it. Yes, these are easy to make at home but safety is important, always use protective gear while making it.

Iodine crystals

A photograph of the tiny Iodine crystals.

It is perhaps one of the most fun compounds that you can use to prank your friends or increase a child’s fascination with science. But it should also be understood that all of the experiments are done with not more than a pinch of NI3, anything more than that might be problematic and even cause injuries.



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