What
do you understand by (a) inert pair effect (b) allotropy and
(c) catenation?
What do you understand by (a) inert pair effect (b) allotropy and (c) catenation?
(a) Inert
pair effect
As
one moves down the group, the tendency of s-block
electrons to participate in chemical bonding decreases. This effect
is known as inert pair effect. In case of group 13 elements, the
electronic configuration is ns2
np1
and their group valency is +3.
However, on moving down the group, the +1 oxidation state becomes
more stable. This happens because of the poor shielding of the ns2
electrons by the d-
and f-
electrons. As a result of the poor shielding, the ns2
electrons are held tightly by the nucleus and so, they cannot
participate in chemical bonding.
(b) Allotropy
Allotropy
is the existence of an element in more than one form, having the same
chemical properties but different physical properties. The various
forms of an element are called allotropes.
For example, carbon exists in three allotropic forms: diamond,
graphite, and fullerenes.
(c) Catenation
The
atoms of some elements (such as carbon) can
link with one another through strong covalent bonds to form long
chains or branches. This property is known as catenation. It is most
common in carbon and quite significant in Si and S.
(a) Inert pair effect
As one moves down the group, the tendency of s-block electrons to participate in chemical bonding decreases. This effect is known as inert pair effect. In case of group 13 elements, the electronic configuration is ns2 np1 and their group valency is +3. However, on moving down the group, the +1 oxidation state becomes more stable. This happens because of the poor shielding of the ns2 electrons by the d- and f- electrons. As a result of the poor shielding, the ns2 electrons are held tightly by the nucleus and so, they cannot participate in chemical bonding.
(b) Allotropy
Allotropy is the existence of an element in more than one form, having the same chemical properties but different physical properties. The various forms of an element are called allotropes. For example, carbon exists in three allotropic forms: diamond, graphite, and fullerenes.
(c) Catenation
The atoms of some elements (such as carbon) can link with one another through strong covalent bonds to form long chains or branches. This property is known as catenation. It is most common in carbon and quite significant in Si and S.
