Beryllium and aluminium exhibit many properties which are similar. But the two elements differ in
- (A)exhibiting maximum covalency in compound✓ Correct
- (B)exhibiting amphoteric nature in their oxides
- (C)forming covalent halides
- (D)forming polymeric hydrides
Answer: (A)
Solution
Beryllium and aluminium lie on a diagonal of the periodic table and share many traits: both give amphoteric oxides, both form covalent halides, and both are linked by the diagonal relationship. Where they part is in maximum covalency. Beryllium has only four orbitals in its valence shell and so is limited to a covalency of four, whereas aluminium can call on its 3d orbitals to go higher. That difference in maximum covalency is the real point of contrast.
JEE Main · 2004 · 24 Apr 2004 · Offline · Single correct option