Answer;
-Their metallic properties increase and their atomic radii increase
Explanation;
-Group 15 is also called the nitrogen family. It consists of the elements nitrogen, phosphorus, arsenic, antimony, moscovium and bismuth. The atomic radius of these elements increases from Nitrogen to Bismuth.
-Moving down the group, the ionic radii, and atomic radii increases. This is because of the expansion of another main energy level in each progressive element.
-Moving down a group, metallic character increases. On the other hand, the ionization enthalpy of the elements decreases due to an increase in their nuclear size.
