Q.1
The first emission line in the atomic spectrum of hydrogen in the Balmer series appears at ... [ pb. PMT 1996]
  • a)
  • b)
  • c)
  • d)
Q.2
Which of the following statements is incorrect? [ AMU 1997]
  • a) Cathode rays carry negative charge
    ch-1_qn-405choice_img_no1.png
  • b) frequency of X-ray is higher than that of microwaves
    ch-1_qn-405choice_img_no2.png
  • c)Unit for wave number is m-1
    ch-1_qn-405choice_img_no3.png
  • d)Threshold frequency is the same for all metals
    ch-1_qn-405choice_img_no4.png
Q.3
Number of nodal plane 'd' orbital has .... [ KCET 1996]
  • a) 1
  • b) 2
  • c)3
  • d)0
Q.4
The charge of the atom having 17 protons, 18 neutrons and 18 electrons is [ KCET 1994]
  • a) +1
  • b) -1
  • c) -2
  • d) Zero
Q.5
The maximum number of electrons in an atom with l=2 and n=3 is ..[PMP PET 1998]
  • a)2
  • b) 6
  • c)12
  • d)10
Q.6
When the value of azimuthal quantum number , l=2, value of 'n' will be .... [ CPMT 1995]
  • a) 3
  • b) 4
  • c)5
  • d)any one of these
Q.7
The heaviest particle is ....[ DPMT 1994]
  • a) Meson
  • b) Neutron
  • c)Electron
  • d)Proton
Q.8
The number of electrons and neutrons of an element is 18 and 20 respectively. Its mass number is .... [CPMT 1997]
  • a) 2
  • b) 17
  • c) 37
  • d) 38
Q.9
Which of the following is the cause of late discovery of neutron? [ AIIMS 1998]
  • a)Neutron is charge less particle
  • b) Neutron is highly unstable particle
  • c)neutron in the nucleus moves very fast
  • d)All of these
Q.10
What do you mean by degenerate orbitals? ... [ CBSE PMT 19996]
  • a) Orbitals having equal energy
  • b) Orbitals having equal wave function
  • c)Orbital having equal energy but different wave function
  • d)Orbitals having equal energy and equal wave function
Q.11
Consider the following ionsNi2+Co2+Cr2+Fe3+ Atomic number Cr=24, Fe - 16, Co=27, Ni=28 The correct sequence of the increasing order of the number of unpaired electrons is ....
  • a) 1, 2, 3, 4
  • b) 4, 2, 3, 1
  • c) 1, 3, 2, 4
  • d) 3, 4, 2, 1
Q.12
Wavelength associated with electron motion ... [ BHU 1998]
  • a)increases with increase in speed of electron
  • b) remains same irrespective of speed of electron
  • c)decreases with increase of speed of electron
  • d)is zero
Q.13
Which orbital of carbon can absorb photon but not emit it?{CPMT 1997]
  • a) 1s
  • b) 2s
  • c)3p
  • d)2p
Q.14
Atomic weight of an element is not necessarily whole number because... [ DCE 1994]
  • a) It contains electrons, protons and neutrons
    ch-1_qn-419choice_img_no1.png
  • b) It contains allotropic forms
    ch-1_qn-419choice_img_no3.png
  • c) atoms are no longer considered indivisible
    ch-1_qn-419choice_img_no4.png
  • d) it contains isotopes
Q.15
Planck's constant has the same dimensions as that of ... [ AIIMS 1998]
  • a)power
  • b) work
  • c)radiation energy
  • d)angular momentum
Q.16
The value of quantum numbers n, l, and m for 5th electron of Born will be
  • a) n=1, l=0, m=-1
  • b) n=2, l=1, m=-1
  • c)n=2, l=2, m=-1
  • d)n=1, l=2, m=-1
Q.17
The hydride ion is isoelectric with ..... [ AFMC 1995]
  • a) H+
  • b) He+
  • c)He
  • d)Be
Q.18
Electron configuration of four metals are given below. Which of the corresponding element would be most paramagnetic? [ AMU 1997]
  • a) 1s2, 2s2, 2p6
  • b) 1s2, 2s2 2p1
  • c) 1s2, 2s2, 2p5
  • d) 1s2, 2s2 2p4
Q.19
An electron has magnetic quantum number as -3, what is its principal quantum number
  • a)1
  • b) 2
  • c)3
  • d)4
Q.20
The electron configuration of 21Sc is ...{BHU 1997]
  • a) 1s2 2s2 2p6 2s2 3p64s23d1
  • b)1s2 2s2 2p6 2s2 3p64s13d2
  • c)1s2 2s2 2p6 2s2 3p64s03d3
  • d)1s2 2s2 2p6 2s2 3p64s23d2
Q.21
Which of the following has maximum number of unpaired electrons? [ IIT 1996]
  • a) Mg2+
  • b) Ti3+
  • c)V3+
  • d)Fe2+
Q.22
Bohr's radius of Hydrogen atom is ... [ Haryana CEET 1994]
  • a) 0.529 × 10-8 m
  • b) 0.529 ×10-10 m
  • c) 5.29 ×10-8 m
  • d) 5.29 × 10-10 m
Q.23
the electrons identified by quantum numbers n and l (i) n=4, l=1 (ii) n=4, l=0 (iii) n=3 , l=2 (iv) n=3, l=1 can be placed in order of increasing energy, from the lowest to highest, as
  • a)(iv) < (ii) < (iii) <(i)
  • b) (ii) < (iv) < (i) < (iii)
  • c)(i) < (iii) < (ii) < (iv)
  • d)(iii) < (i) < (iv) < (ii)
Q.24
The outer electronic configuration of 3s2 3p5 is possessed by... [ KECT 1997]
  • a) O
  • b) Cl
  • c)Br
  • d)Ar
Q.25
The paramagnetic character follows the order .... [ CBSE MPT 1997]
  • a) Mg > Cr > Zn
  • b) Fe > Zn >Co
  • c)Cr > Fe > Zn
  • d)Hg > Mn > Fe
Q.26
Bohr's model was modified by ... [ EAMCET 1995]
  • a) Sommerfeld
  • b) Rutherford
  • c) Dalton
  • d) Pauli
Q.27
ratio of mass of proton and electron is ... [ BHU 1998]
  • a)infinite
  • b) 1.8 × 10+3
  • c)1.8
  • d)none of these
Q.28
Brackett series are produced when the electrons from outer orbits jump to .... [ Pb CET 1997]
  • a) 2 nd orbit
  • b) 3 rd orbit
  • c)4 th orbit
  • d)5 th orbit
Q.29
heisenberg's Uncertainty Principle is applicable to ... [ BHU 1994]
  • a) atoms only
  • b) electrons only
  • c)nucleus only
  • d)any moving object
Q.30
An element M has an atomic mass 19 and atomic number 9, its ion is represented by [ IIT 1996]
  • a) M+
  • b) M2+
  • c) M-
  • d) M2-
Q.31
Which of the following has more unpaired d-electrons? [ CBSE PMT 1999]
  • a)Zn+
  • b) Fe3+
  • c)Cu3+
  • d)Cu+
Q.32
The energy of an electron in the first Bohr orbit of H atom is -13.6 eV. the possible value(s) of the excited state(s) for electrons in Bohr orbits of hydrogen is (are) .. [ IIT 1998]
  • a) -3.4 eV
  • b) - -4.2 eV
  • c)-6.8 eV
  • d)+6.8 eV
Q.33
the configuration 1s2, 2s2 2p5 3s1 shows .....[AIIMS 1997]
  • a) ground state of fluorine
  • b) excited state of fluorine
  • c)excited state of Neon atom
  • d)excited sate of O2-
Q.34
Azimuthal quantum number determines the .... [ BHU 1995]
  • a) size
  • b) spin
  • c) orientation
  • d) angular momentum of orbitals
Q.35
Which is not true with respect to cathode rays? [ kerala CEE 2001]
  • a)A stream of electron
  • b) Charged particles
  • c)Move with speed same as that of light
  • d)can be deflected by magnetic fields
Q.36
In H atom electron jumps from 3rd to 2nd energy level, the energy released is ... [ AFMC 1997]
  • a) 3.03 ×10-19 J/atom
  • b) 1.03 ×10-19 J/atom
  • c)3.03 ×10-12 J/atom
  • d)6.06 ×10-19 J/atom
Q.37
if the planck's constant h=6.6×10-34 Js, the de Broglie wave length of a particle having momentum of 3.3×10-24 kg m s-1 will be ... [ Pb CET 1998]
  • a) 0.002 Ao
  • b)0.5 Ao
  • c)2.0 Ao
  • d)500 Ao
Q.38
Two particles A and B are in motion. if the wavelength associated with the particle A is 5.0 ×10-8 m, the wavelength of particle B having momentum half of A is
  • a) 2.5×10-8 m
  • b) 1.25×10-8 m
  • c) 1.0×10-7 m
  • d) 1.0×10-8 m
Q.39
For which of the following species, Bohr's theory is not applicable? [ DEC 2000]
  • a)Be3+
  • b) Li2+
  • c)He2+
  • d)H
Q.40
Chloride ion and potassium ion are isoelectronic then [ KCET 2002]
  • a) their size are same
  • b) Chloride ion is bigger than potassium ion
  • c)potassium ion is relatively bigger
  • d)depends upon the other cation or anion
Q.41
The wave number of first line of Balmaer series of hydrogen is 15200 cm-. The wave number of first Balmaer line of Li2+ ion is ..[ IIT 1992]
  • a)15200 cm-1
  • b) 60800 cm-1
  • c)76000 cm-1
  • d)136800 cm-1
Q.42
In the Bohr's orbit, what is the ratio of total kinetic energy and total energy of the electrons ... [ Rajasthan PMT 2002]
  • a) -1
  • b) -2
  • c) +1
  • d) +2
Q.43
Identify the least stable among the following ... [ IIT 2002]
  • a)Li-
  • b) Be-
  • c)B-
  • d)C-
Q.44
In a Bohr's atomic model, when an electron jumps from n=3 to n=1 how much energy will be emitted? [ CBSE PMT 1996]
  • a) 2.15 ×10-11 ergs
  • b) 2.389 ×10-12 ergs
  • c)0.239 ×10-10 erg
  • d)0.1936 ×10-10 erg
Q.45
The work function of a metal is 4.2eV. If radiations of 2000Ao fall on the metal then the kinetic energy of the fastest photo electron is
  • a) 1.6 ×10-19 J
  • b) 16 ×1010 J
  • c)3.2 ×10-19 J
  • d)6.4 × 10-10 J
Q.46
An electron moving with velocity 'v' is found to have a certain value of de-broglie wave length. the velocity to be possessed by the neutron to have the same de-Broglie wave length is ...
  • a) 1840/v
  • b) 1840v
  • c) v/1840
  • d) v
Q.47
Which of the following atom has no neutron in its nucleus? [ CPMT 2000]
  • a)Helium
  • b) Lithium
  • c)Protium
  • d)Tritium
Q.48
The frequency of yellow light having wavelength 600nm is ... [MPPMT 2002]
  • a) 5.0 ×1014Hz
  • b) 2.5 ×107 Hz
  • c)5 ×107 Hz
  • d)2.5 × 1014 Hz
Q.49
The energy of the first electron in helium will be ...[ Bihar CEE 2002]
  • a) -13.6 eV
  • b) -54.4 eV
  • c)-5.44 eV
  • d)zero
Q.50
The wavelength associated with golf ball weighing 200g and moving at speed of 5m/h is of the order... [ IIT 2001]
  • a) 10-10 m
  • b) 10-20 m
  • c) 10-30 m
  • d) 10-40 m
0 h : 0 m : 1 s