Structure Of Atom – Multiple Choice Questions

Q1. The ground state electron configuration of Fe is:

  1. 1s2 2s3s2 3p6  3d10
  2. 1s2 2s2 2p6 3s2 3p6 3d8
  3. 1s2 2s2 2p6 3s2 3p6 4s2
  4. 1s2 2s2 2p6 3s2 3p6 4s3d6

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Q2. The energy of a photon of light has what kind of proportionality to its frequency and its wavelength?

  1. directly, directly
  2. inversely, inversely
  3. inversely, directly
  4. directly, inversely

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Q3. The de Broglie wavelength of a tennis ball of mass 50 g moving with a velocity of 10 m/s is approximately

  1. 0.132 x 10-30 m
  2. 0.132 x 10-20 m
  3. 0.132 x 10-22 m
  4. 0.132 x 10-32 m

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Q4. The ejected electrons from the surface of metal in photoelectric effect are called

  1. Electron
  2. Photoelectrons
  3. Proton
  4. Neutron

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Q5. Which of the subshells below do not exist due to the constraints upon the azimuthal quantum number?

  1. 2d
  2. 2s
  3. 2p
  4. 4d

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Q6. Which statement regarding an orbital is FALSE?

  1. An orbital is three dimensional.
  2. An electron shell consists of a collection of orbitals with the same principal quantum number.
  3. An orbital may be designated with the letters K,L,M,N.
  4. An orbital describes the region in which the possibility of finding an electron is maximum.

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Q7.The charge on electron was determined by

  1. Bohr
  2. Milliken
  3. Schrodinger
  4. Crooks

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Q8. Which of the following is a possible electronic configuration?

  1. 1s2s2p6
  2. 1s2s2p3s3p3d7
  3. 1s2s2p3s3d12
  4. 1s2s2p3s3p4

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Q9. Quantum mechanics is based on a fundamental equation which is called

  1. Newton’s law
  2. Schrodinger equation
  3. Equation of state
  4. Boyle’s law

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Q10. De Broglie proposed that –

  1. Matter consists of microscopic particles
  2. Matter should exhibit particle nature Only
  3. Matter should exhibit both particle and wave nature
  4. Matter consists of microscopic paricles

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Q11. Which of the following sets of orbitals is arranged in order of increasing energy?

  1. 3d < 4s < 4p < 5s < 4d
  2. 4s < 3d < 4p < 5s < 4d
  3. 4s < 3d < 4p < 5s < 4d
  4. 3d < 4s < 4p < 4d < 5s

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Q12. The total energy of an electron in the nth orbit of a hydrogen atom is given by the formula En = -13.6 eV/n2. What does the negative energy for an electron indicate?

  1. Electrons have both wave and particle-like properties.
  2. The electron has a negative charge.
  3. The electron is far away from nucleus.
  4. Energy of electron in an atom is lower than the energy of an electron far away from nucleus.

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Q13. The uncertainty principle states that

  1. It is impossible to determine mass of light particles
  2. It is impossible to know anything with certainty
  3. It is impossible to know the exact position and momentum of an electron simultaneously
  4. There can only be one uncertain digit in a reported number

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Q14. The fundamental subatomic particle neutron was discovered by

  1. Rutherford
  2. Max Planck
  3. Heisenberg
  4. Chadwick

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Q15. For Balmer series, the initial state n1 is:

  1. 1
  2. 2
  3. 3
  4. 4

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Q16. The shape of the px orbital is:

  1. Spherical
  2. Octahedral
  3. Dumb-bell
  4. Double Dumb-bell

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Q17. What is the wavelength of a photon that has energy of 5.25 x 10-19J?

  1. 3.79 x 10-7
  2. 2.64 x 106
  3. 2.8 x 1023
  4. 4.21 x 10-24

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Q18. In the absorption spectrum, the wavelengths which are absorbed are missing and they appear as

  1. Bright lines
  2. Dark lines
  3. Bright bands
  4. Light bands

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Q19. Calculate the value of principal quantum number for the subshell notation 3p?

  1. 1
  2. 2
  3. 3
  4. 4

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Q20. Which of the following subatomic particles is responsible for the spectrum of radiation emitted by an element or a compound?

  1. Proton
  2. Electron
  3. Neutron
  4. Photon

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Q21. A proton and an electron are both travelling at the same speed. What can we conclude about their de Broglie wavelengths?

  1. It is impossible to determine the relative sizes of their wavelengths from the information given.
  2. They will both have the same wavelength.
  3. The wavelength of the proton will be shorter than that of the electron.
  4. The wavelength of the electron will be shorter than that of the proton.

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Q22. Total number of orbitals in a shell is given by

  1. n3
  2. 3n2
  3. n2
  4. n4

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Q23. For l = 2, how many orbitals are possible?

  1. 1
  2. 2
  3. 3
  4. 5

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Q24. What is incorrect about electromagnetic radiations?

  1. They require a medium to travel
  2. They can travel in vacuum
  3. Oscillating electric and magnetic fields are perpendicular to each other
  4. Oscillating electric and magnetic fields are perpendicular to the direction of propagation of the wave

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Q25. How much energy is needed to ionize a hydrogen atom if electron is present in n=1 orbit?

  1. 13.6 eV
  2. 10.2 eV
  3. 3.4eV
  4. 1 eV

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Q26. A sub shell with l = 2 can take up a maximum of:

  1. 5 electrons
  2. 3 electrons
  3. 8 electrons
  4. 10 electrons

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Q27. Which one of the following represents a wrong set of quantum numbers for an electron in an atom? (arranged as n, l, m, and s)

  1. 2, 1, -1, -1/2
  2. 1, 0, 0, ±1/2
  3. 3, 3, 3, ±1/2
  4. 5, 4, – 3, +1/2

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Q28. The Pauli exclusion principle states that:

  1. Both the position of an electron and its momentum cannot be known simultaneously very accurately.
  2. The wavelength and mass of a subatomic particle are related by I = h/m v
  3. The wavelength of a photon of light times its frequency is equal to the speed of light.
  4. No two electrons in the same atom can have the same set of four quantum numbers.

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Q29. Which one of the following represents an acceptable possible set of quantum numbers (in the order n, l, mand mfor an electron in an atom?

  1. 2, 1, -1, 1/2
  2. 2, 1, 0, 0
  3. 2, 1, 2, 1/2
  4. 2, 0, 1, -1/2

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Q30. If there are three electrons in p-subshell, which one of the following is the correct electronic configuration for these electrons?

  1. px2 py1 pz0
  2. px2 py0 pz1
  3. pxpy1 pz2
  4. px1 py1 pz1

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Q31. Simultaneous determination of exact position and momentum of an electron is:

  1. Possible
  2. Not possible
  3. Sometimes possible and sometimes impossible
  4. Momentum cannot be determined

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Q32. For the value of principal quantum number 3 the possible values for azimuthal quantum number will be:

  1. 1,2,3
  2. 0,1,2,3
  3. 0,1,2
  4. -3,-2,-1,0,+1,+2,+3

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Q33. Which of the following set of quantum numbers represents the highest energy of an atom?

  1. n=3, l=1, m=1, ms = +1/2
  2. n=3, l=2, m=1, ms= +1/2
  3. n=4, l=0, m=0, ms= +1/2
  4. n=3, l=0, m=0, ms= +1/2

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Q34. A Na lamp emits yellow light with a wavelength of 589 nm. What is the energy of a single photon in this light?

  1. 3.37 x 10-19 Joules.
  2. 1.12 x 10-25 Joules.
  3. 5.09 x 1015 Joules.
  4. 5.09 x 1014 Joules.

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Q35. Uncertainty in the position of an electron (mass 9.1 x 10-31 kg) moving with a velocity of 300 ms-1, accurate upto 0.001% will be:

  1. 19.2 x 10-2 m
  2. 5.76 x 10-2 m
  3. 1.92 x 10-2 m
  4. 3.84 x 10-2 m

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Q36. Which one of the following electronic configurations depict an oxygen atom?

  1. 1s22s22p2
  2. 1s22s22p23s2
  3. 1s22s22p1
  4. 1s22s22p4

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Q37. Which one of the following orbitals can hold only two electrons?

  1. 2p
  2. 3s
  3. 4d
  4. 5f

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Q38. Which quantum numbers must be the same for the orbitals so that they are designated to be degenerate in a one-electron system (like hydrogen)?

  1. n and m
  2. n and l only
  3. l and m
  4. m only

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Q39. What is the frequency of a photon that has an energy of 3.7 x 10-18J?

  1. 5.6 x 1015
  2. 1.8 x 10-16
  3. 2.5 x 10-15
  4. 0.55 X 10+16

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Q40. At what speed (m/s) must a 3.0 mg object be moving in order to have a de Broglie wavelength of 5.4 x 10-29 m?

  1. 4.1
  2. 2.0 x 1012
  3. 3.9 x 10-4
  4. 1.6 x 10-28

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