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 8 of 47
- A. when electrons jump down to 2nd- orbit
- B. when electrons jump down to 3rd- orbit
- C. when electrons jump down to 4th- orbit
- D. when electrons jump down to 5th- orbit
Explanation: The Pfund series consists of hydrogen-electron transitions that end at the fifth energy level, n = 5, with photons emitted in the infrared…
Correct answer: when electrons jump down to 5th- orbit- A. Zeeman effect
- B. Stark effect
- C. Photoelectric effect
- D. Compton effect
Explanation: The Stark effect is the splitting or shifting of spectral lines when atoms are placed in a strong electric field.
Correct answer: Stark effect- A. Lyman
- B. Paschen
- C. Pfund
- D. Brackett
Explanation: When an electron falls to the first orbit, n = 1, the emitted spectral lines belong to the Lyman series.
Correct answer: Lyman- A. Different wavelength
- B. Different colours
- C. Different intensities
- D. all have little contribution
Explanation: A spectrum is produced when radiation is separated according to wavelength, producing distinct wavelengths or corresponding frequencies.
Correct answer: Different wavelength145. Splitting of spectral lines when atom is subjected to magnetic field is called _______________?
- A. Zeemans effect
- B. Starks effect
- C. Photo electric effect
- D. Compton effect
Explanation: The splitting of spectral lines in the presence of a magnetic field is called the Zeeman effect.
Correct answer: Zeemans effect- A. Brighter
- B. Darker
- C. Colourless
- D. Hard to locate
Explanation: When atoms absorb selected frequencies of energy, electrons move to higher energy levels and remove those wavelengths from transmitted…
Correct answer: Darker- A. 1.0073
- B. 1.0087
- C. 5.485 x 10^-4
- D. 9.1 x 10^-31
Explanation: The conversion from kg to a.m.u is; 1 a.m.u= 1.66 x 10-27 The mass of an electron is 9.11x10-31 kg; this value should be learned for the…
Correct answer: 5.485 x 10^-4- A. 1.602 x 10^-31 C
- B. 1.602 x 10^-27 C
- C. 1.602 x 10^-19 C
- D. 1.602 x 10^-11 C
Explanation: This is a factual recall question. The charge on a proton is equal to +1e, where e is the elementary charge having a value of 1.602 x…
Correct answer: 1.602 x 10^-19 C- A. Electron
- B. Proton
- C. Neutron
- D. Meson
Explanation: Meson, any member of a family of subatomic particles composed of a quark and an antiquark.
Correct answer: Electron- A. Deuterium
- B. Tritium
- C. Ortho hydrogen
- D. None of these
Explanation: Ortho-para hydrogen are spin isomers of hydrogen . Hydrogen only has 3 isotopes. Refer to the image below:
Correct answer: Ortho hydrogen- A. Electron, neutrino
- B. Electron, proton
- C. Proton, neutrino
- D. Neutron, proton
Explanation: Option D is the best choice because neutrons and protons have mass most close to each other.
Correct answer: Neutron, proton- A. Hydrogen
- B. Helium
- C. Carbon
- D. Neon
Explanation: When a hydrogen atom loses its electron, it becomes a hydrogen ion, specifically a hydrogen cation (H+).
Correct answer: Hydrogen- A. Electron
- B. Neutron
- C. Nucleus
- D. None
Explanation: The charge-to-mass ratio (e/m) is a measure of the charge of a particle relative to its mass.
Correct answer: Electron- A. MgO
- B. CuO
- C. Al2O3
- D. ZnS
Explanation: MgO is not commonly used as phosphor materials for producing flashes upon electron impact.
Correct answer: ZnS- A. Neutron
- B. Mass number
- C. Atomic number
- D. Electrons
Explanation: A neutron is another subatomic particle found in the nucleus of an atom.
Correct answer: Electrons- A. Atomic number
- B. Mass number
- C. Hydrogen
- D. None
Explanation: The atomic number, denoted by the letter 'Z', represents the number of protons in the nucleus of an atom.
Correct answer: Atomic number157. charge on proton is
- A. Positive
- B. Negative
- C. Neutral
- D. None
Explanation: The charge on a proton is positive because it is a fundamental particle with a positive electric charge, and its presence, along with…
Correct answer: Positive- A. 1836
- B. 1829
- C. 1882
Explanation: The mass of a proton is 1836 times heavier than that of electron due to the strong nuclear force on the proton.
Correct answer: 1836- A. Hydrogen gas
- B. Helium
- C. Neon
- D. Air
Explanation: The positive particle obtained from hydrogen is the lightest among all the other positive particles and is called a proton having mass…
Correct answer: Hydrogen gas- A. [Ar] 3d4 4s2
- B. [Ar] 3d5 4s1
- C. [Ar] 3d6 4s1
- D. [Ar] 3d1 4s2
Explanation: It is [Ar] 3d⁵ 4s¹This happens in Cr, as one 4s electron moves to the 3d sublevel. But why?
Correct answer: [Ar] 3d5 4s1