Atomic Structure
103 questions · Click an option and press Check Answer to reveal the result
Uncertainty in position of a particle of 25 gram in space is 10–5 m. Hence uncertainty in velocity (m/sec) is (h = 6.6 × 10–34 J sec)
2.1 × 10–28
2.1 × 10–34
0.5 × 10–34
5 × 10–24
Which of the following statements are correct?
(A) Work function (ϕ) is same for all metals.
(B) Specific charge (e/m) of electron is greater than that of proton.
(C) The electronic configuration of Cu is violating Aufbau principle
(D) Bohr's model can be applied to multielectron system.
(E) Ar, S²⁻, Ca²⁺ and K⁺ are isoelectronic species Choose the correct option
The threshold frequency for a metal is 7.0 × 1014 s-1. Calculate the kinetic energy of an electron emitted when radiation of frequency 1.0 × 1015 s-1 hits the metal.
1.98 × 10-18 J
1.98 × 10-19 J
2 × 10-16 J
2 × 10-19 J
If an electron is present in n = 6 level. How many spectral lines would be observed in case of H atom
10
15
20
25
Match List I with List II.
List I List II
(A) Rydberg constant (I) 6.626 × 10⁻³⁴ Js
(B) Planck’s constant (II) 3 × 10⁸ ms⁻¹
(C) Velocity of light (III) 9.1 × 10⁻³¹ kg
(D) Mass of electron (IV) 109, 677 cm⁻¹
Choose the correct answer from the options given below:
The ionization energy of H-atom is 13.6 eV. The ionization energy of Li+2 ion will be -
13.6 eV
27.2 eV
54.4 eV
122.4 eV
If the radius of the 3rd orbit of Li2+ ion is x, then find the radius of the 1st orbit of He+ ion in terms of x;
Given below are two statements
Statement I: Frequency of He⁺ ion of 2nd line of Balmer series is equal to that of 1st line of Paschen series of He⁺ ion.
Statement II: Radius of 2nd Bohr orbit of He⁺ ion is equal to that of 2nd Bohr orbit of H atom.
In the light of above statements, choose the most appropriate answer from the options given below.
N3- , F- , Na+
Be , Al3+ , Cl-
Ca2+ , Cs+ , Br-
Na+ , Ca2+ , Mg2+
What is potential energy of an electron present in N-shell of the Be3+ ion
The ionization energy of He+ is 19.6 × 10–18 J atom–1. The energy of the first stationary state of Li+2 will be
21.2 × 10–18 J/atom
44.10 × 10–18 J/atom
63.2 × 10–18 J/atom
84.2 × 10–18 J/atom
Given below are two statements, one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): Threshold frequency is the maximum frequency required for the ejection of electron from the metal surface.
Reason (R): Threshold frequency is the characteristic of a metal. In the light of the above statements, choose the correct answer from the options given below:
A 0.66 kg ball is moving with a speed of 100 m/s. The associated wavelength will be : (h = 6.6×10–34 J s)
6.6 × 10–34 m
1.0 × 10–35 m
1.0 × 10–32 m
6.6 × 10–32 m
Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R
Assertion A: According to de-Broglie, the wavelengths associated with electrons and other subatomic particles can be detected experimentally.
Reason R: The wavelength associated with any material particle is directly proportional to its mass. In the light of the above statements, choose the correct answer from the options given below:
The wavelength of light associated with a photon of energy 3.3 × 10-19 J is:
6.0 × 10-7 m
5.0 × 10-7 m
4.0 × 10-7 m
3.0 × 10-7 m
A ball of mass 200 g is moving with a velocity of 10 m s-1. If the error in measurement of velocity is 0.1%, the minimum uncertainty in its position is:
3.3 × 10-31 m
3.3 × 10-27 m
5.3 × 10-25 m
2.64 × 10-32 m
The uncertainty in the momentum of a particle is 2.5 × 10–16 g cm s–1. With what accuracy can its position be determined?
(h = 6.625 × 10–27 erg. s, i.e., g cm2 s–1)
2.11 × 10–12 cm
21.1 × 10–12 cm
2.11 × 10–10 cm
2.11 × 10–8 cm
Total number of electrons present in Cr24 and Cu29 having quantum number l = 2 and m = 0