Question

Beryllium, the first member of group 2, shows an anomalous behavior as compared to Mg and the rest of the members on account of
A. exceptionally small atomic and ionic radii
B. high ionization enthalpy
C. absence of vacant d-orbitals in its valence shell
D. all of these

Answer 1

Correct Answer - D
Because of high ionization (due to small atomic radius) and high charge density (due to small ionic radius), Be forms covalent compounds in the anhydrous state which are easily hydrolysed. Due to the absence of vacant d-orbitals, Be dows not exhibit coordination number more that four while other members of group 2 can have a coordination number of six by using the vacant d-orbitals in their valence shell.
`[Be(H_(2)O)_(4)]Cl_(2)` and `[Ca(H_(2)O)_(6)]Cl_(2)`