Q6 of 8 Page 25

Certain subshells of an atom are given below. 2s, 2d, 3f, 3d, 5s, 3p

a) Which are the subshells that are not possible?


b) Give the reason.

a) 2d, 3f

b) In the first shell, there is only 1s subshell because this shell can have a maximum of only 2 electrons. So 1p subshell does not exist.


In the second shell, there are 2s and 2p subshells because this shell can have a maximum of 8 electrons. So 2d does not exist.


In the third shell, there are 3s, 3p, and 3d subshells because this shell can have a maximum of 18 electrons. So 3f does not exist.


In fourth shell, there are 4s, 4p, 4d and 4f subshells because this shell can have maximum of 32 electrons.


More from this chapter

All 8 →
3

Pick out the wrong ones from the subshell electronic configurations given below.

a) 1s2 2s2 2p7


b) 1s2 2s2 2p2


c) 1s2 2s2 2p5 3s1


d) 1s2 2s2 2p6 3s2 3p6 3d2 4s1


e) 1s2 2s2 2p6 3s2 3p6 3d2 4s2

 4

The element X in group 17 has 3 shells. If so,

a) Write the subshell electronic configuration of the element.


b) Write the period number


c) What will be the chemical formula of the compound formed if the element X reacts with element Y of the third period which contains one electron in the p subshell?

 5

The element Cu with atomic number 29 undergoes chemical reaction to form an ion with oxidation number +2.

a) Write down the subshell electronic configuration of this ion.


b) Can this element show variable valency? Why?


c) Write down the chemical formula of one compound formed when this element reacts with chlorine (17Cl).

 1

A part of the periodic table is given below. The symbols of elements given in the columns are not real.


a) Which are the elements having only one electron in the 4s subshell?


b) Which is the element in s block with the smallest atomic radius?


c) Which are the elements likely to form coloured compounds?


d) Which is the metal with the highest reactivity?


e) Which is the element with the least reactivity?


f) Which is the element in which the last electron is filled in the 4p sub shell? Find its atomic number.


g) Frame as many questions as possible to get each element in this table as the answer.