WorksheetsStructure of atom
Total questions: 17
Worksheet time: 9mins
According to Bohr’s theory of the hydrogen atom, the angular momentum of an electron is
mvr = nh/2π
mvr = nh/4π
mvr = nh/π
mvr = nh/4π
How many unpaired electrons are present in Ni²⁺?
8
6
3
2
On moving down the group, the shielding effect
Increases
Decreases
Remains the same
None of these
Indicate the number of unpaired electrons in the Cl atom.
0
5
3
1
Calculate the number of radial nodes present in the 3d sub-shell.
0
1
2
4
What is the total number of orbitals associated with the principal quantum number n = 4?
10
16
12
8
How many electrons are present in 3d orbitals of Fe³⁺?
6
4
5
3
Identify the sub-shell with highest energy.
5s
4d
5p
4f
Spin quantum number of the outermost electron of Al is ………
+1/2
-1/2
+1
-1
Assertion: There are 5 electrons in the 3d sub-shell of Cr.
Reason: Half-filled sub-shells are more stable.
Both A and R are true and R is the correct explanation of A
Both A and R are true but R is not the correct explanation of A
A is true but R is false
A is false but R is true
For the electrons of oxygen atom, which of the following statements is correct?
Zeff for an electron in a 2s orbital is the same as Zeff for an electron in a 2p orbital
An electron in the 2s orbital has the same energy as an electron in the 2p orbital
Zeff for an electron in 1s orbital is the same as Zeff for an electron in a 2s orbital
The two electrons present in the 2s orbital have spin quantum numbers ms but of opposite spin
11. Which of the following statements concerning the quantum numbers are correct?
Angular quantum number determines the three dimensional shape of the orbital.
The principal quantum number determines the orientation and energy of the orbital.
Magnetic quantum number determines the size of the orbital.
Spin quantum number of an electron determines the orientation of the spin of electron relative to the chosen axis.
12. Out of the following pairs of electrons, identify the pairs of electrons present in degenerate orbitals.
(i) n = 3 ,l = 2 ,ml = - 2 ,ms= - 1/2
(ii) n = 3, l = 2, ml= - 1 ,ms= - 1/2
(i) n = 3, l = 1 ,ml = 1, ms= 1/2
(ii) n = 3, l = 2 ,ml= 1 ,ms = 1/2
(1) n = 4, l = 1, ml = 1 ,ms= 1/2
(ii) n = 3, l = 2, ml= l, ms= 1/2
(i) n = 3, l = 2 ml= 2 ,ms = - 1/2
(ii) n = 3, l = 2 ,ml= 2 ms= 1/2
14. Assertion (A): All isotopes of a given element show the same type of chemical behaviour.
Reason (R): The chemical properties of an atom are controlled by the number of electrons in the atom.
Both A and R are true and R is the correct explanation of A
Both A and R are true but R is not the correct explanation of A
A is true but R is false
A is false R is true
1Assertion (A): Black body is an ideal body that emits and absorbs radiations of all frequencies.
Reason (R): The frequency of radiation emitted by a body goes from a lower frequency to higher frequency with an increase in temperature.
Both A and R are true and R is the correct explanation of A
Both A nd R are true but R is not the correct explanation of A
A is true but R is false
A is false but R is true
Assertion (A): It is impossible to determine the exact position and exact momentum of an electron simultaneously.
Reason (R): The path of an electron in an atom is clearly defined.
Both A and R are true and R is the correct explanation of A
Both A nd R are true but R is not the correct explanation of A
A is true but R is false
A is false but R is true
Wavelengths of different radiations are given below:
lambda(A) = 300nm
lambda(B) = 300micrimetre
lambda(C) = 3nm
lambda(D) = 30A
Arrange these radiations in the increasing order of their energies.
B < A < C = D
A<B<C=D
A=B<C=D
A>B>C=D
