HARD
Earn 100

A single electron system has ionization energy 11180 kJ mol-1. The number of protons in the nucleus of the system will be__________.

Important Questions on Structure of Atom

EASY
Match List - I (Electromagnetic wave type) with List - II (Its association/application) and select the correct option from the choices given below the lists :
 
  List - I   List - II
(a) Infrared waves (i) To treat muscular strain
(b) Radio waves (ii) For broadcasting
(c) X - rays (iii) To detect fracture of bones
(d) Ultraviolet rays (iv) Absorbed by the ozone layer of the atmosphere
EASY
The energy of the em waves is of the order of 15 keV. To which part of the spectrum does it belong?
MEDIUM
If the shortest wavelength in Lyman series of hydrogen atom is A, then the longest wavelength in Paschen series of He+ is
MEDIUM

For any given series of spectral lines of atomic hydrogen, let  Δv-=v-max-v-min  be the difference in maximum and minimum wave number in cm-1

The ratio Δv-Lyman/Δv-Balmar is

MEDIUM

Given below are two statements :
Statement I : According to Bohr's model of an atom, qualitatively the magnitude of velocity of electron increases with decrease in positive charges on the nucleus as there is no strong hold on the electron by the nucleus.
Statement II : According to Bohr's model of an atom, qualitatively the magnitude of velocity of electron increases with decrease in principle quantum number.

In the light of the above statements, choose the most appropriate answer from the options given below:

EASY
Arrange the following electromagnetic radiations per quantum in the order of increasing energy:
A:  Blue light
B:  Yellow light
C:  X-ray
D:  Radiowave
MEDIUM
Which of the following statements is false?
MEDIUM
The shortest wavelength of H atom in the Lyman series is λ1. The longest wavelength in the Balmer series of He+ is :
MEDIUM

The longest wavelength of light that can be used for the ionisation of lithium atom Li in its ground state is x×10-8 m. The value of x is (Nearest Integer)

(Given : Energy of the electron in the first shell of the hydrogen atom is -2.2×10-18 J; h=6.63×10-34Js and c=3×108 ms-1)

MEDIUM
In hydrogen atom, the minimum energy required to excite an electron from 2nd  orbit to the  3rd  orbit is
EASY
Which of the following series of transitions in the spectrum of hydrogen atom falls in visible region?
EASY
The radius of the first Bohr orbit of a hydrogen atom is 0.53×10-8 cm. The velocity of the electron in the first Bohr orbit is
MEDIUM
The ratio of the shortest wavelength of two spectral series of hydrogen spectrum is found to be about 9. The spectral series are:
EASY
If microwaves, Xrays, infrared, gamma rays, ultraviolet, radio waves and visible parts of the electromagnetic spectrum are denoted respectively by MXIGUR and V the following is the arrangement in ascending order of the wavelength
MEDIUM
For the Balmer series, in the spectrum of H atom, v-=RH1n12-1n22, the correct statements among I to IV are,
I As wavelength decreases, the lines in the series converge.
II The integer n1 is equal to 2.
III The lines of the longest wavelength correspond to n2=3.
IV The ionization energy of hydrogen can be calculated from the wave number of these lines.
EASY
Two series of spectral lines of atomic hydrogen which do not belong to infrared spectral region are
EASY
The region in the electromagnetic spectrum where the Balmer series lines appear is:
MEDIUM

Question Image

The electron in the nth  orbit of Li2+  is excited to (n+1) orbit using the radiation of energy 1.47×10-17 J (as shown in the diagram). The value of n is ___________

Given : RH=2.18×10-18 J

 

MEDIUM
What will be the first ionization energy of Be atom ? Consider the first ionization energy of H atom as 13.6 eV.
MEDIUM

The ionization energy of gaseous Na atoms is 495.5 kJ mol-1. The lowest possible frequency of light that ionizes a sodium atom is 

(h=6.626×10-34 Js, NA=6.022×1023 mol-1)