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 27 of 47
- A. 2
- B. 16
- C. 4
- D. 18
Explanation: Option D suggests that the total number of lobes in all the d orbitals is 18.
Correct answer: 18- A. A
- B. B
- C. C
- D. D
Explanation: If more than one degenerate orbitals are available then electrons go one by one with same spin.
Correct answer: C523. _ are such nuclei of an element that have the same atomic number Z, but have different mass number.
- A. Isotopes
- B. Isobars
- C. Isomers
- D. Isotherms
Explanation: Correct option is A. Isotopes of an element has the same number of protons but different numbers of neutrons.
Correct answer: Isotopes- A. 6
- B. 2
- C. 8
- D. 10
- E. 18
Explanation: n is the principal quantum number and indicates the number of shells. n = 2 indicates that the second shell is being discussed.
Correct answer: 6- A. 9.108 × 10−28 kg
- B. 9.108 × 10−25 g
- C. 9.108 × 10−31 kg
- D. Too less to be measured
Explanation: 9.108 × 10^−31 kg: This option represents the approximate weight of an electron.
Correct answer: 9.108 × 10−31 kg- A. 7 or 8
- B. 11 or 12
- C. 5 or 6
- D. 10 or 11
Explanation: Copper (Cu) has an atomic number of 29, meaning it has 29 electrons in its neutral state.
Correct answer: 11 or 12527. Choose the correct set of quantum numbers for the Ne atom's electron of the second excited state:
- A. 2, 0, 0, +1/ 2
- B. 3, 2, 1, +1/ 2
- C. 3, 0, 0, +1/ 2
- D. 3,1, 2, +1/ 2
Explanation: Principal Quantum Number (n): 3 (Third energy level) Azimuthal Quantum Number (ℓ): 0 (s orbital) Magnetic Quantum Number (mℓ): 0 (One of…
Correct answer: 3, 0, 0, +1/ 2- A. dxy
- B. dyz
- C. dz2
- D. dz2-y2
Explanation: The correct option is c) dz2.The d-orbital which is bi-lobed with a collar is represented by the dz2 orbital.Option a) dxy: The dxy…
Correct answer: dz2- A. 11
- B. 14
- C. 15
- D. 16
Explanation: The correct option is b) 14.To determine the number of electrons present in the M-shell of an element with an atomic number of 26, we need…
Correct answer: 14- A. Sc+2
- B. Ti+4
- C. Cr+2
- D. Mn+6
Explanation: Titanium (Ti) has an atomic number of 22. If it loses 4 electrons to become Ti+4, its electronic configuration becomes: 1s² 2s² 2p⁶ 3s²…
Correct answer: Ti+4- A. np2x, np1Y, np0Z
- B. np1x, np1Y, np1Z
- C. np2x, np0Y, np1Z
- D. np0x, np1Y, np2Z
Explanation: Half-filled and completely filled arbitas are relatively more stable.Option B suggests that each of the three electrons is in a different…
Correct answer: np1x, np1Y, np1Z- A. Ar
- B. CI-
- C. S
- D. P3-
Explanation: The electronic configuration of sulfur is [Ne]3s² 3p⁴. The given configuration matches the electron distribution of sulfur (S), with 16…
Correct answer: S- A. Hund's rule
- B. Pauli exclusion principle
- C. Aufbau principle
- D. n+l rule
Explanation: Option A is correct.If more than one degenerate orbitals are available then electrons go one by one with same spin is called hund's…
Correct answer: Hund's rule- A. 2(2/-1)
- B. 2(21+1)
- C. 2(/+1)
- D. 2/+1
Explanation: Option B is correct.The maximum number of electrons in a subshell is given by 2(2l + 1).
Correct answer: 2(21+1)- A. 2
- B. 1/2
- C. 4
- D. 1/4
Explanation: Option A is correct.The number of electrons with n = 2, l = 0 in an atom with 35 nucleons and an atomic number of 17 is 2.
Correct answer: 2- A. Electricity
- B. Anode
- C. Gas molecule
- D. Cathode
Explanation: High speed electrons collide with the gas molecules and knock off electrons from them making them positively charged .
Correct answer: Gas molecule- A. 4p
- B. 4f
- C. 4d
- D. 5s
Explanation: Principal Quantum number shows the orbit is 4 and Azimuthal quantum number 2 shows that electron is in d subshell. So, option C is correct.
Correct answer: 4d- A. n
- B. m
- C. l
- D. s
Explanation: The spin quantum number, denoted as (m), is not obtained by solving Schrödinger's wave equation.
Correct answer: s- A. 4
- B. 6
- C. 5
- D. 7
Explanation: The total number of d-electrons in an atom is determined by its atomic number.
Correct answer: 6- A. 2p
- B. 2d
- C. 4s
- D. 1s
Explanation: The Azimuthal quantum number (l) specifies the shape of an orbital in an atom.The azimuthal quantum number can take on integer values from…
Correct answer: 2d