The following observations are made about two hypothetical elements A and B: The A—A and B—B bond lengths in elemental A and B are 2.36 and 1.94 A. respectively. A and B react to form the binary compound AB2. which has a linear structure (that is^B-A-B = 180°). Based on these statements, predict the separation between the two B nuclei in amolecule of AB2.

Solution Step 1 Bonding atomic radius is half of the bond length in bonded molecules Given that the bond length in A-A molecule is 2.36A ° 2.36 Thus atomic radius of A= 2 =1.18A ° Similarly given that the bond length of B-B molecule is 1.94 A ° 1.94 Thus atomic radius of B= 2 =0.97A ° Thus A-B bond length=Atomic radius of A+Atomic radius of B =1.18A +0.97A ° =2.15A °