Question

Which one of these are the simplest pnictogen hydride?
A. Ammonia
B. alkyl amine
C. Phosphine
D. Water

Answer 1

Hint: All nitrogen group elements are called pnictogen elements. Nitrogen, phosphorus, arsenic, antimony and bismuth belong to the nitrogen group. The hydride of a nitrogen group is called a pnictogen hydride.

Complete step by step answer:
- Pnictogen is a Greek word, which means to choke generator.
- The simplest series of pnictogen hydride has a general molecular formula of $X{{H}_{3}}$ , where X = element from the nitrogen group.
- The chemicals given in the options A, B and C are Ammonia, Alkyl amine and Phosphine is pnictogen hydrides.
- The molecular formulas of options A, B and C are $N{{H}_{3}},R-N{{H}_{2}}\text{ }and\text{ }P{{H}_{3}}$ respectively.
- But in the question it is asked for the simplest pnictogen hydride.
- The simplest pnictogen hydride among the given options is ammonia.
- Therefore the simplest pnictogen hydride among the given options is ammonia.

- So, the correct answer is A.

Additional information:
 - Pnictogen hydrides are water soluble.
- Binary compounds of group-15 are called pnictides.
- Pnictides are diamagnetic and paramagnetic at room temperature.
- Generally Ammonia is produced industrially on a large scale.

Note: The smallest pnictogen among the all nitrogen group (group-15) is nitrogen. Pnictogen hydrides have a general structure of pyramidal. Pnictogen hydrides have no smell and are odorless in their pure form. They will get odor once they contact air. Ammonia has an intense smell of fish or urine and phosphine will give a smell like garlic or fish.