Answer:
Group 15
Explanation:
The elements of group 15 (column) VA of the periodic table all have electron configurations of s2p3 , giving them five valence electrons. These elements include Nitrogen (N), Phosphorus (P), Arsenic (As), Antimony (Sb) and Bismuth (Bi).
The % composition of each element is calculated as follows
= mass of the element/total mass x100
total mass= 73.5+4.2+72.3=150
% composition of C = 73.5/150 x100=49%
% composition of H= 4.2/150 x100= 2.8%
%composition of Cl= 72.3/150 x100= 48.2%