Question

2.0mL of ammonium hydroxide solution is slowly added to 0.1g of I₂ and is stirred for 5 minutes. A moist red precipitate is formed and allowed to cool for 1 hour. This is the synthesis of an explosive: NI₃•NH₃

1. Write plausible reaction(s) for the formation of NI₃•NH₃

2. Assuming that in the explosion reaction all of the nitrogen in NI₃•NH₃ ends up as N₂, write a reasonable equation for the overall reaction

3. NI₃ is more reactive than NCl₃; NF is stable. Suggest an explanation

4. Why are N-H single bonds more stable than most other N-X bonds?

Show all work for all please :)

Answer 1

We are here discussing about trinitrogen iodide also known as contact explosive due to its behavior it is an extremely unstable compound and explodes when it is touched.

Let's solve all these questions one by one

01. Reaction for synthesis of NI₃. NH₃

as we know we make this product by reacting ammonium hydroxide and iodine

The balanced reaction is

5NH₃ + 3 I₂ ---> NI₃NH₃ + 3NH₄I

Ammonia in this reaction is obtained from ammonium hydroxide

02. Reaction for explosion of NI₃. NH₃

The explosive reaction takes place as

8NI₃​​​​​​.NH₃ --> 5N₂ + 6NH₂I + 9I₂

This is a balanced chemical reaction for the decomposition or explosive reaction of nitrogen triiodide

03.

​​​​​​as we see the periodic table we can understand as we go down the group the size of elements increase

In halides flourine is smallest in size and iodine in big in size compared to chlorine bromine and iodine

The fluorine size is comparable to the nitrogen and it forms bond between 2p of florine and 2p of nitrogen so it is stable

In case of chlorine the size of chlorine and nitrogen is not comparable and also the bond formation is also not stable between these two and makes it unstable

The same case follows for iodine and nitrogen making it extremely unstable and hence explosive in nature.

04.

nitrogen has small size and very high electronegativity similarly hydrogen is also small in size and has high electronegativity so it can form stable covalent bonds with nitrogen

But in case of nitrogen and halogens their sizes are not comparable making their bonds unstable in nature (except fluorine)

So the NH bonds are more stable

I hope this helps. If you have any query or want more detailed explanation feel free to ask in the comments section below.