Q.1
on Q199) Consider the following sets of quantum numbers Which of the following sets of quantum number is not possible? [AIPMT (Prelims)-2007]
Sr n l m s
(a) 3 0 0 +1/2
(b) 2 2 1 +1/2
(c) 4 3 –2 3 -2 -1/2
(d) 1 0 –1 0 -1 -1/2
(e) 3 2 3 +1/2
  • a) a and c
  • b) b, c and d
  • c) a, b, c and d
  • d) b, d and e
Q.2
Assertion : K.E. of two subatomic particles, having same de-Broglie’s wavelength is same. Reason : de-Broglie’s wavelength is directly related to mass of subatomic particles.
  • a) Both Assertion and Reasoning are true and Reasoning is correct explanation of Assertion
  • b) Both are correct but Reason is not explanation of Assertion
  • c) Assertion is correct but Reason is wrong
  • d) Both Assertion and Reason are incorrect.
Q.3
If uncertainty in position and momentum are equal, then uncertainty in velocity is [AIPMT (Prelims)-2008]
  • a)
    ch-1_qn-201choice_img_no1.png
  • b)
    ch-1_qn-201choice_img_no2.png
  • c)
    ch-1_qn-201choice_img_no3.png
  • d)
    ch-1_qn-201choice_img_no4.png
Q.4
The ratio of specific charge of an electron to that of a proton is
  • a) 1 : 1
  • b) 1837 : 1
  • c) 1 : 1837
  • d) 2 : 1
Q.5
In an atom, which has 2K, 8L, 18M and 2N electrons in the ground state. The total number of electrons having magnetic quantum number, m = 0 is
  • a) 6
  • b) 10
  • c) 7
  • d) 14
Q.6
Assuming the velocity to be same, the wavelength of the waves associated with which of the following particles would be maximum?
  • a) An electron
  • b) A proton
  • c) An α-particle
  • d) A deutro
Q.7
Assertion : Energy of electron is taken negative. Reason : Energy of electron at infinity is zero.
  • a) Both Assertion and Reasoning are true and Reasoning is correct explanation of Assertion
  • b) Both are correct but Reason is not explanation of Assertion
  • c) Assertion is correct but Reason is wrong
  • d) Both Assertion and Reason are incorrect.
Q.8
For the transition from n = 2 → n = 1, which of the following will produce shortest wavelength?
  • a) H atom
  • b) D atom
  • c) He+ ion
  • d) Li2+ ion
Q.9
In a Bohr’s model of an atom, when an electron jumps from n = 1 to n = 3, how much energy will be emitted or absorbed?
  • a) 2.389 × 10–12 ergs
  • b) 0.239 × 10–10 ergs
  • c) 2.15 × 10–11 ergs
  • d) 0.1936 × 10–10 ergs
Q.10
The wavelength associated with a ball of 200 g and moving with a speed of 5 m/hour is of the order of
  • a) 10–10 m
  • b) 10–20 m
  • c) 10–30 m
  • d) 10–40 m
Q.11
If threshold wavelength (λo) for ejection of electron from metal is 330 nm, then work function for the photoelectric emission is
  • a) 6 × 10–10 J
  • b) 1.2 × 10–18 J
  • c) 3 × 10–19 J
  • d) 6 × 10–19 J
Q.12
Which of the following orbital is with the four lobes present on the axis?
  • a) dz2
  • b) dxy
  • c) dyz
  • d) dx2-y2
Q.13
A 0.66 kg ball is moving with a speed of 100 m/s. The associated wavelength will be (h = 6.6 × 10–34 Js) [AIPMT (Mains)-2010]
  • a) 6.6 × 10–32 m
  • b) 6.6 × 10–34 m
  • c) 1.0 × 10–35 m
  • d) 1.0 × 10–32 m
Q.14
Assertion : Isotopes of an element have almost similar chemical properties. Reason : Isotopes have same electronic configuration.
  • a) Both Assertion and Reasoning are true and Reasoning is correct explanation of Assertion
  • b) Both are correct but Reason is not explanation of Assertion
  • c) Assertion is correct but Reason is wrong
  • d) Both Assertion and Reason are incorrect.
Q.15
En = –313.6/n2 kcal/mole. If the value of E = –34.84 kcal/mole, to which value does ‘n’ correspond?
  • a) 4
  • b) 3
  • c) 2
  • d) 1
Q.16
on Q214) Consider the following sets of quantum number Which of the following sets of quantum number is not possible?
Sr n l m s
(i) 3 0 0 +1/2
(ii) 2 2 1 +1/2
(iii) 4 3 -2 –1/2
(iv) 1 0 -1 -1/2
(v) 3 2 3 +1/2
  • a) (i), (ii), (iii) and (iv)
  • b) (ii), (iv) and(v)
  • c) (i) and (iii)
  • d) (ii), (iii) and (iv)
Q.17
How many 3d electrons can have spin quantum number (-1/2)
  • a) 5
  • b) 7
  • c) 8
  • d) 10
Q.18
If each orbital can hold a maximum of 3 electrons. The number of elements in 2nd period of periodic table
  • a) 27
  • b) 9
  • c) 18
  • d) 12
Q.19
The Bohr orbit radius for the hydrogen atom (n = 1) is approximately 0.530 Å. The radius for the first excited state (n = 2) orbit is (in Å)
  • a) 4.77
  • b) 1.06
  • c) 0.13
  • d) 2.12
Q.20
Who modified Bohr’s theory by introducing elliptical orbits for electron path?
  • a) Rutherford
  • b) Thomson
  • c) Hund
  • d) Sommerfield
Q.21
The ion that is isoelectronic with CO is
  • a) CN–
  • b) N2+
  • c) O2–
  • d) N2–
Q.22
The value of Planck's constant is 6.63 × 10–34 Js. The speed of light is 3 × 1017 nm s–Which value is closest to the wavelength in nanometer of a quantum of light with frequency of 6 × 1015 s–1? [NEET-2013]
  • a) 25
  • b) 50
  • c) 75
  • d) 10
Q.23
Which of the following has maximum number of unpaired d-electrons?
  • a) N3+
  • b) Fe2+
  • c) Zn+
  • d) Cu+
Q.24
The first emission line in the atomic spectrum of hydrogen in the Balmer series appears at
  • a) (5R/36) cm-1
  • b) (3R/4) cm-1
  • c) (7R/144) cm-1
  • d) (9R/400) cm-1
Q.25
Which of the following is not among shortcomings of Bohr’s model?
  • a) Bohr theory could not account for the fine lines in the atomic spectrum
  • b) Bohr theory was unable to account for the splitting of the spectral lines in the presence of magnetic field
  • c) Bohr theory failed for He atom
  • d) It did not give information about energy level
Q.26
According to Bohr’s theory angular momentum of an electron in 6th orbit is
  • a) 2.5h/π
  • b) 6h/π
  • c) 3h/π
  • d) 2.5h/2π
Q.27
Assertion : In third energy level there is no f-subshell. Reason : For n = 3, the possible values of l are 0, 1, 2 and for f-subshell l = 3.
  • a) Both Assertion and Reasoning are true and Reasoning is correct explanation of Assertion
  • b) Both are correct but Reason is not explanation of Assertion
  • c) Assertion is correct but Reason is wrong
  • d) Both Assertion and Reason are incorrect.
Q.28
For which one of the following set of quantum numbers an electron will have the highest energy?
  • a) 3, 2, 1, 1/2
  • b) 4, 2, 1, 1/2
  • c) 4, 1, 0, -1/2
  • d) 5, 0, 0, 1/2
Q.29
Uncertainty in position of an electron (mass = 9.1 × 10–28g) moving with a velocity of 3 × 104 cm/s accurate upto 0.001% will be (Use h/(4π) in uncertainty expression where h = 6.626 × 10–27 erg-s)
  • a) 5.76 cm
  • b) 7.68 cm
  • c) 1.93 cm
  • d) 3.84 cm
Q.30
In the ground state, an element has 13 electrons in its M-shell. The element is
  • a) Manganese
  • b) Cobalt
  • c) Nickel
  • d) Iron
Q.31
Assertion : Orbital angular momentum of (1s, 2s, 3s etc.) all s electrons is same. Reason : Orbital angular momentum depends on orientation of orbitals.
  • a) Both Assertion and Reasoning are true and Reasoning is correct explanation of Assertion
  • b) Both are correct but Reason is not explanation of Assertion
  • c) Assertion is correct but Reason is wrong
  • d) Both Assertion and Reason are incorrect.
Q.32
For principal quantum number n = 5, the total number of orbitals having l = 3 is
  • a) 7
  • b) 14
  • c) 9
  • d) 18
Q.33
The following quantum numbers are possible for how many orbitals : n = 3, l = 2, m = +2?
  • a) 1
  • b) 2
  • c) 3
  • d) 4
Q.34
A p-n photodiode is made of a material with a band gap of 2.0 eV. The minimum frequency of the radiation that can be absorbed by the material is nearly [AIPMT (Prelims)-2008]
  • a) 20 × 1014 Hz
  • b) 10 × 1014 Hz
  • c) 5 × 1014 Hz
  • d) 1 × 1014 Hz
Q.35
Which transition of Li2+ is associated with same energy change as n = 6 to n = 4 transition in He+?
  • a) n = 3 to n = 1
  • b) n = 8 to n = 6
  • c) n = 9 to n = 6
  • d) n = 2 to n = 1
Q.36
According to the Bohr Theory, which of the following transitions in the hydrogen atom will give rise to the least energetic photon? [AIPMT (Mains)-2011]
  • a) n = 6 to n = 5
  • b) n = 5 to n = 3
  • c) n = 6 to n = 1
  • d) n = 5 to n = 4
Q.37
The de-Broglie wavelength of an electron travelling with 10% of velocity of light is equal to (mass of electron =9.1× 10-31 kg)
  • a) 242.4 pm
  • b) 24.2 pm
  • c) 2.42 pm
  • d) 2.424 pm
Q.38
The correct set of four quantum numbers for the valence electron of rubidium atom (Z = 37) is [AIPMT (Prelims)-2012]
  • a) 5, 0, 0, 1/2
  • b) 5, 1, 0, 1/2
  • c) 5, 1, 1, 1/2
  • d) 6, 0, 0, 1/2
Q.39
In a hydrogen atom, if the energy of electron in the ground state is –x eV., then that in the 2nd excited state of He+ is
  • a) –x eV
  • b) -4x/9 eV
  • c) +2x eV
  • d) -9x/4 eV
Q.40
The orientation of an atomic orbital is governed by [AIPMT (Prelims)-2006]
  • a) Azimuthal quantum number
  • b) Spin quantum number
  • c) Magnetic quantum number
  • d) Principal quantum number
Q.41
The orbital angular momentum of a p-electron is given as [AIPMT (Mains)-2012]
  • a)
    ch-1_qn-239choice_img_no1.png
  • b)
    ch-1_qn-239choice_img_no2.png
  • c)
    ch-1_qn-239choice_img_no3.png
  • d)
    ch-1_qn-239choice_img_no4.png
Q.42
In hydrogen atom, energy of first excited state is –3.4 eV. Then find out KE of same orbit of hydrogen atom
  • a) +3.4 eV
  • b) +6.8 eV
  • c) –13.6 eV
  • d) +13.6 eV
Q.43
What is the maximum numbers of electrons that can be associated with the following set of quantum numbers? n = 3, l = 1 and m = –1 [NEET-2013]
  • a) 6
  • b) 4
  • c) 2
  • d) 10
Q.44
With which of the following configuration an atom has the lowest ionization enthalpy ? [AIPMT (Prelims)-2007]
  • a) 1s2 2s2 2p6
  • b) 1s2 2s2 2p5
  • c) 1s2 2s2 2p3
  • d) 1s2 2s2 2p5 3s1
Q.45
In Bohr series of lines of hydrogen spectrum, the third line from the red end corresponds to which one of the following inter-orbit jumps of the electron for Bohr orbits in an atom of hydrogen?
  • a) 3 → 1
  • b) 5 → 2
  • c) 2 → 5
  • d) 3 → 2
Q.46
The angular momentum of electron in 'd' orbital is equal to ... [ AIMPMT 2015]
  • a) 0ħ
  • b) √6 ħ
  • c) √2 ħ
  • d) 2√3 ħ
Q.47
The number of photons of light of wavelength 7000Å equivalent to 1 J are
  • a) 3.52 × 10–18
  • b) 3.52 × 1018
  • c) 50,000
  • d) 10,0000
Q.48
Which of the following contains maximum number of electrons in the antibonding molecular orbitals
  • a) O2
  • b) O22-
  • c)O2-
  • d)O2+
Q.49
Number of spectral lines in Balmer series when an electron return from 7th orbit to 1st orbit of hydrogen atom
  • a) 5
  • b) 6
  • c) 21
  • d) 15
Q.50
Which of the following transition will emit maximum energy in hydrogen atom?
  • a) 4f → 2s
  • b) 4d → 2p
  • c) 4p → 2s
  • d) All have same energy
0 h : 0 m : 1 s