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 29 of 47
- A. 4+2=6
- B. 5+2=7
- C. 3+3=6
- D. 4+3=7
Explanation: The value of n+l for 4f subshell is : 4+3=7where n=4 and l=3(for f)
Correct answer: 4+3=7- A. Na+1 is smaller in size as compared to Mg+2
- B. Sodium has lost its valence shell while Mg hasn't
- C. Both have 10 electrons
- D. Both have 11 and 12 electrons respectively
Explanation: Na+ = 11 - 1 = 10 Mg+2 = 12 - 2 = 10 Hence, both have 10 electrons.
Correct answer: Both have 10 electrons- A. 2nd
- B. 5th
- C. 1st
- D. 3rd
Explanation: 5th shell i.e n=5 is the most suitable option among all the other options which shows that the electron in this shell is farthest from the…
Correct answer: 5th- A. The no. of electrons in valence shell.
- B. Relative energies of shells.
- C. Relative energies of subshells.
- D. Distribution of electrons in orbitals.
Explanation: The Aufbau principle provides information about the order in which electrons fill atomic orbitals, but it does not explicitly specify the…
Correct answer: The no. of electrons in valence shell.- A. S
- B. Cl+2
- C. Cl-2
- D. K+1
Explanation: The valence shell electronic configuration shows that the element has 6 valence electrons,therefore it belongs to the 6th group.The n…
Correct answer: S- A. 4s
- B. 2s
- C. 3d
- D. 3p
Explanation: According to the Auf bau principle,latest electron goes to the the highest energy orbital.The increasing energy order for the orbitals…
Correct answer: 3d- A. Any s-orbital
- B. Any s or p-orbital
- C. Any s or d-orbital
- D. Any p-orbital
Explanation: A p orbital has directional character with its three mutually prependicular orbitals labelled as px,py,pz.
Correct answer: Any p-orbital- A. L-shell
- B. s-orbitals
- C. p-subshells
- D. M-shell
Explanation: Sodium has electronic configuration : 1s2,2s2,2p6,3s1.Potassium has electronic configuration : 1s2,2s2,2p6,3s2,3p6,4s1.This shows that…
Correct answer: L-shell- A. X>Y>Z
- B. X<Y<Z
- C. X=Y>Z
- D. X>Y<Z
Explanation: To determine the number of electrons present in the 'M' shells of elements X, Y, and Z, we need to consider the electron configuration of…
Correct answer: X<Y<Z- A. 3s and 3p orbitals are of higher energy than 3d orbital
- B. 3p orbital is higher in energy than 3d orbital
- C. 3s orbital is higher in energy than 3p orbital
- D. 3d orbitals are higher in energy than 3s and 3p orbitals
Explanation: The increasing order of energy of subshells of 3rd shell is : 3s<3p<3d ,hence 3d has more energy than 3s and 3p both.
Correct answer: 3d orbitals are higher in energy than 3s and 3p orbitals- A. 90%
- B. 98%
- C. 95%
- D. 100%
Explanation: An electron orbital is most commonly defined as the radius of the sphere that encloses 95% of the total electron probability.
Correct answer: 95%- A. 6.626 x 10^-34 KJs
- B. 6.262 x 10^-34 Js-1
- C. 6.626 x 10^-34 Js
- D. 6.262 x 10^-34 KJs
Explanation: The value of planck constant is 6.626 x 10^-34Js.
Correct answer: 6.626 x 10^-34 Js- A. First
- B. Second
- C. Third
- D. Fourth
Explanation: The radius of any orbit can be calculated by using formula n^2 (0.53) For 1st orbit; (1)^2(0.53) = 0.53Å For 2nd orbit; (2)^2(0.53) =…
Correct answer: Third- A. Equal to 1836 electron
- B. Equal to positron
- C. Equal to electron
- D. Equal to 1836 neutron
Explanation: The mass of proton is 1836 times that of electron. STB Pg- 79 Hence, option A is correct.
Correct answer: Equal to 1836 electron- A. Paschen series
- B. Balmer series
- C. Lyman series
- D. Pfund series
Explanation: Lyman series-Correct answer: This series corresponds to transitions where electrons fall to the first energy level (n=1) and lies in the…
Correct answer: Lyman series- A. p orbital
- B. s orbital
- C. d orbital
- D. f orbital
Explanation: Orientation of orbitals are given by magnetic quantum number. By using formula; (2l + 1) we can calculate the orientations of orbitals in…
Correct answer: s orbital- A. -1 to 1
- B. -1 to 2
- C. -1 to 3
- D. -1 to 4
Explanation: When the azimuthal quantum number (l) is 1, the magnetic quantum number (m) can take on values ranging from -1 to 1.
Correct answer: -1 to 1- A. 7
- B. 5
- C. 1
- D. 3
Explanation: Dumbbell-like orbitals, such as p orbitals, can move in three directions corresponding to the x, y, and z axes.
Correct answer: 3- A. n=L1
- B. I=n-2
- C. I= n-1
- D. n = 1-2
Explanation: The relationship between the principal quantum number (n) and the azimuthal quantum number (l) is l = n - 1.
Correct answer: I= n-1- A. Ar
- B. Cl
- C. Na
- D. S
Explanation: The ground state electronic configuration given as 1s², 2s², 2p6, 3s², 3p6, corresponds to the electronic configuration of the element…
Correct answer: Ar