Free Atomic Structure MCQs with Answers
922 Atomic Structure MCQs from Chemistry, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Atomic structure covers the discovery of the proton, Planck's quantum theory, hydrogen emission spectra and the evidence for quantized energy levels. You will use quantum numbers to describe orbitals, distinguish s, p, d and f orbital shapes, and write electronic configurations, including the correct order of electron filling.
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922 questions · page 30 of 47
- A. 7f
- B. 7d
- C. 7p
- D. 7s
Explanation: According to the Aufbau principle, electrons are filled in the following order: 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d…
Correct answer: 7p- A. [Ar] 4s0, 3d6
- B. [Ar] 4s2, 3d6
- C. [Ar] 4s2, 3d4
- D. [Ar] 4s2, 3d5
Explanation: The correct electronic configuration of iron (II) ion (Fe2+) is [Ar] 4s0, 3d6.
Correct answer: [Ar] 4s0, 3d6- A. 5
- B. 3
- C. 7
- D. 1
Explanation: Option C is the correct choice. To determine the number of orientations of a sub-shell with quantum numbers n=4 and l=3, we use the…
Correct answer: 7- A. Balmer series
- B. Pfund series
- C. Bracket series
- D. Paschen series
Explanation: Option A is correct.The photon of the lowest wavelength is related to the Balmer series.
Correct answer: Balmer series- A. He
- B. N2
- C. Ne
- D. H2
Explanation: Option D is correct. The maximum e/m ratio for positive rays is achieved with H2 because it is the lightest atom, resulting in the highest…
Correct answer: H2- A. Zn+2
- B. Cu+
- C. Ti+3
- D. Fe+3
Explanation: Titanium has an atomic number of 22, and its electron configuration is [Ar]3d24s2[Ar] 3d^{2} 4s^{2}[Ar]3d24s2.
Correct answer: Ti+3- A. 4p 5s 4d 5p 6s 4f 5d
- B. 4p 4s 4d 5p 5s 5f 6d
- C. 4p 4s 4d 5p 5s 4f 5d
- D. 4p 3s 4d 5p 6s 4f 5d
Explanation: This sequence follows the correct order of filling orbitals according to the Aufbau principle.
Correct answer: 4p 5s 4d 5p 6s 4f 5d- A. 24
- B. 30
- C. 32
- D. 34
Explanation: Number of neutrons = Atomic weight - Atomic number Number of neutrons = 56 amu - 26 = 30 amuTherefore, the number of neutrons in the…
Correct answer: 30- A. nh/2π
- B. n^2h/2π
- C. h/2π
- D. n^3h/2π
Explanation: This is the correct answer. According to Bohr's theory, the angular momentum of an electron in a hydrogen atom is quantized and can only…
Correct answer: nh/2π- A. 3
- B. 1
- C. 5
- D. 7
Explanation: This is the correct answer. Let's break down the quantum numbers:n = 2: This indicates that the electrons are in the second principal…
Correct answer: 3- A. Lyman series
- B. Balmer series
- C. Pfund series
- D. Brackett series
Explanation: The Balmer series is a series of spectral lines in the hydrogen atom spectrum that lies in the visible region of the electromagnetic…
Correct answer: Balmer series- A. 3.39A
- B. 4.761A
- C. 5.29 x 10^11 A
- D. 9.7A
Explanation: The radius of an electron orbit in a hydrogen atom can be calculated using the Bohr model, which gives the radius of the nth orbit as:rn =…
Correct answer: 4.761A- A. Canal rays
- B. Magnetic rays
- C. Quantum
- D. Photon rays
Explanation: Positive rays, also known as canal rays, are streams of positively charged particles, typically ions or cations, that are produced when a…
Correct answer: Canal rays- A. (2,1,0)
- B. (2,1,1)
- C. (3,1,1)
- D. (3,0,0)
Explanation: (3,1,1) - Correct. The unpaired electron in chlorine is in the 3p orbital, where n=3, l=1, and m=1.
Correct answer: (3,1,1)- A. It is at a higher energy level than a 4p orbital but has the same shape
- B. It is occupied by one electron in an isolated Zn atom
- C. It can hold a maximum of 10 electrons
- D. It has the highest energy of the orbitals with principal quantum number 4
Explanation: It can hold a maximum of 10 electrons - Correct. A d-orbital can hold up to 10 electrons (5 orbitals, each accommodating 2 electrons).
Correct answer: It can hold a maximum of 10 electrons- A. 1.6726 × 10⁻²⁷ kg
- B. 9.54 × 10⁷ C/kg
- C. Show deflection under electric & magnetic fields
- D. Do not cause mechanical motion
Explanation: Do not cause mechanical motion - Correct. Canal rays do cause mechanical motion, so this statement is false.
Correct answer: Do not cause mechanical motion- A. This condition reduces friction
- B. This condition creates more energy
- C. This condition results in zero magnetism and removes the charge of the electron
- D. This condition results in less repulsion and opposite magnetic fields
Explanation: Opposite spins reduce repulsion and result in a stable orbital configuration due to opposing magnetic fields.
Correct answer: This condition results in less repulsion and opposite magnetic fields- A. Paschen series
- B. Pfund series
- C. Bracket series
- D. Lyman series
- E. Balmer series
Explanation: The above equation is of the Balmer series, thus option E is the correct answer.
Correct answer: Balmer series- A. Neutron highly penetrating, velocity is equal to that of light. Remain un deflected in magnetic field
- B. Most penetrating, velocity is equal to that of light no deflection in magnetic field, short wave length, shorter than x-rays
- C. Least penetrating, velocity /o of light deflects in magnetic field helium nucleus
- D. Proton least penetrating, deflects like negative particle in magnetic field
- E. Most penetrating power, velocity less than that light of deflects in magnetic filed they are Electron
Explanation: Most penetrating, velocity is equal to that of light, no deflection in a magnetic field, short wavelength, shorter than x-rays.
Correct answer: Most penetrating, velocity is equal to that of light no deflection in magnetic field, short wave length, shorter than x-rays- A. s-orbital
- B. s, p, d& f orbital
- C. s & p orbital
- D. All options are correct
- E. s ,p & d orbital
Explanation: The possible orbitals are the s, p, and d orbitals. The s orbital is spherical in shape, while the p orbitals are dumbbell-shaped and can…
Correct answer: s ,p & d orbital