1
|
Atomic
radii of elements of third period are given below:
|
|
|
||||||||||||||||
(a)
|
Arrange
them in the decreasing order of their atomic radii.
|
||||||||||||||||
Ans:
|
They are
arranged in the decreasing order of their atomic radii as follows:
|
||||||||||||||||
(b)
|
Are they
arranged as in the periodic table?
|
||||||||||||||||
Ans:
|
Originally
they are not arranged as in the periodic table. But, after arranging them in
the decreasing order of theit atomic radii, they are arranged as in the
periodic table.
|
||||||||||||||||
(c)
|
Which
are the atoms of highest and lowest atomic radii?
|
||||||||||||||||
Ans:
|
The atom
with highest atomic radius is Sodium (190 pm) and the atom with lowest atomic
radius is Chlorine (99 pm).
|
||||||||||||||||
(d)
|
What
trend is observed in the atomic radii in a period from left to right?
|
||||||||||||||||
Ans:
|
As we move
from left to right in a period, the atomic radius gradually decreases. As we
move from left to right, electrons are added. This increases the nuclear
attraction and electrons tend to pull closer. This decreases the atomic
radius.
|
2
|
Atomic
radii of group 17 are given below:
|
|
|
||||||||||
(a)
|
Arrange
them in the increasing order of their atomic radii.
|
||||||||||
Ans:
|
They are
arranged in the increasing order of their atomic radii as follows:
|
||||||||||
(b)
|
Are they
arranged as in the periodic table?
|
||||||||||
Ans:
|
Originally
they are not arranged as in the periodic table. But, after arranging them in
the increasing order of theit atomic radii, they are arranged as in the
periodic table.
|
||||||||||
(c)
|
Which
are the atoms of highest and lowest atomic radii?
|
||||||||||
Ans:
|
The atom
with highest atomic radius is Iodine (133 pm) and the atom with lowest atomic
radius is Fluorine (72 pm).
|
||||||||||
(d)
|
What
trend is observed in the atomic radii down the group?
|
||||||||||
Ans:
|
As we move
from top to bottom in a group, the atomic radius gradually increases.. As we
move from top to bottom in a group, new shells are added. This increases the
atomic radius.
|