What are the products obtained when ammonia is reacted with excess chlorine? (a) \(\mathrm{N}_{2}\) and \(\mathrm{NH}_{4} \mathrm{Cl}\) (b) \(\mathrm{N}_{2}\) and \(\mathrm{NCl}_{3}\) (c) \(\mathrm{NCl}_{3}\) and \(\mathrm{HCl}\) (d) \(\mathrm{N}_{2}\) and \(\mathrm{HCl}\)

Chemical reactions are the processes by which substances interact to form new compounds with different physical and chemical properties. At its core, a chemical reaction involves the rearrangement of atoms. When we look at the reaction between ammonia (H_3) and chlorine (Cl_2), it's important to note that these two reactants are combining in a way that their atoms reconfigure to produce new substances.

Different conditions can lead to varied types of reactions and products. For instance, the reaction between ammonia and chlorine can result in several different products depending on the ratio of reactants and the environment in which the reaction takes place. When ammonia reacts with an excess of chlorine, a specific type of reaction occurs known as oxidation and chlorination, which leads to a unique set of products.

Oxidation and chlorination are two key processes that often occur in chemical reactions involving chlorine. Oxidation refers to the loss of electrons by a molecule, atom, or ion, while chlorination involves the addition of chlorine to a molecule.

In the context of the reaction between ammonia and excess chlorine, these processes work together. Chlorine is a powerful oxidizing agent as well as a chlorinating agent. When chlorine comes into contact with ammonia, the chlorine atoms cause the ammonia to lose electrons - that is to oxidize. Simultaneously, chlorine atoms are added to the resulting compound. This dual action is what leads to the formation of nitrogen trichloride (Cl_3) and hydrogen chloride (HCl), as opposed to other potential products that may form under different reaction conditions.

Nitrogen trichloride (Cl_3) is a product of the reaction between ammonia and chlorine when chlorine is in excess. The formation of nitrogen trichloride is particularly interesting because it is a clear demonstration of the combination of oxidation and chlorination processes.

Cl_3 is formed when three chlorine atoms are added to a nitrogen atom from ammonia. This process not only involves the addition of chlorine (chlorination) but also the removal of hydrogen atoms from ammonia, which is an oxidation of the nitrogen. This compound is quite volatile and has to be handled with care due to its explosive properties. It is also a clear example of how careful control of reaction conditions can lead to the formation of distinct products. The formation of Cl_3 alongside HCl is the correct answer to our original exercise, demonstrating the selective nature of chemical reactivity under specific conditions.