Question
Discuss the diagonal relationship of boron with silicon.
Solution
The diagonal relationship is due to the fact that both these elements have almost similar values of atomic radii. electronegativity and ionisation energies. Some important points of similarities are:
(i) Both boron and silicon exhibit typical properties of non-metals i.e. possess high melting and boiling points and are non-conductors of electricity.
(ii) Both elements are semiconductors.
(iii) Both exist in amorphous and crystalline forms.
(iv) Both boron and silicon do not form cations.
(v) Both form weak acids as H3BO3 and H4SiO4.
(vi) Chlorides of both elements get hydrolysed easily.
(vii) Both form metallic compounds known as borides and silicides as:
