Question

Which of the following elements does not show allotropy?

Answer 1

$\text{The trend in allotropy of group}15\text{elements}$

In group $15$, all the elements show allotropy except nitrogen. Nitrogen does not show allotropy due to its weak $N-N$ single bond because of high inter-electronic repulsion of the non-bonding electrons and has less stability to form polymeric structure. Rest elements of group $15$, such as phosphorus, arsenic, antimony, and bismuth, show allotropy due to their ability to form stronger single bonds with themselves.