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 40 of 47
- A. 2.8 × 10−18 J/atom
- B. 0.545 × 10−18 J/atom
- C. −2.18 × 10−18 J/atom
- D. −1312.36 J/atom
Explanation: By using the formula for the energy of an electron in the nth orbitEn=-{me-4Z2/8 ε2 h2 n2}For hydrogen Z=1 and by putting values of…
Correct answer: 0.545 × 10−18 J/atom- A. Aufbau principle
- B. Pauli's exclusion principle
- C. Hund's rule
- D. Le Chatelier's principle
Explanation: Correct option is C. Thus, nitrogen contains three unpaired electrons following Hund's rule of maximum multiplic According to this rule…
Correct answer: Hund's rule- A. n
- B. m
- C. s
- D. I
Explanation: The shape of an orbital is described by the azimuthal quantum number or orbital angular momentum quantum number (l).
Correct answer: I- A. A
- B. B
- C. C
- D. D
Explanation: Option 'B' is correct because the image shown in it is not violating any rule and shows the correct visual representation of the…
Correct answer: B- A. The direction of the electron's spin
- B. The energy level of the electron
- C. The orbital shape of the electron
- D. The number of electrons in an orbital
Explanation: The quantum numbers +1/2 and -1/2 represent the direction of the electron's spin.
Correct answer: The direction of the electron's spin- A. Max Planck
- B. Neil Bohr
- C. J.J. Thomson
- D. Goldstein
- E. James Chadwick
Explanation: James Chadwick is best known for his discovery of the neutron in 1932, a breakthrough that significantly advanced our understanding of…
Correct answer: James Chadwick- A. Faraday's experiment proved the existence of electrons
- B. Crookes tube experiment shows the presence of electrons and protons in the atoms
- C. Radioactivity confirms the presence of electrons and protons
- D. Chadwick experiment shows the presence of neutrons
Explanation: Option D is correct. Chadwick bombarded a sample of beryllium with alpha particles and observed a new form of radiation that was not…
Correct answer: Chadwick experiment shows the presence of neutrons788. A 4s orbital has:
- A. One node
- B. Two nodes
- C. Three nodes
- D. Zero nodes
Explanation: A node is a region in an orbital where the probability of finding an electron is zero. In a 4s orbital, there are no nodes present.
Correct answer: Zero nodes- A. Has a tight structure
- B. Has high density
- C. Has no free electron in the crystal
- D. Is transparent to light
Explanation: A good conductor has a large presence of free electrons, as they are not bonded strongly to the nucleus, and allow conduction of charges…
Correct answer: Has no free electron in the crystal- A. An equal number of electrons and neutrons
- B. An equal number of electrons, protons and neutrons
- C. The number of neutrons is double the number of protons
- D. The number of protons is double the number of neutrons.
Explanation: Tritium is the isotope of hydrogen having mass number 3 and proton number 1.
Correct answer: The number of neutrons is double the number of protons- A. [Xe]4f14, 5d10, 6s1
- B. [Xe]4 f10, 5d10, 6s2
- C. [Xe]4f14, 5d9, 6s2
- D. [Xe]4f14, 5d10, 6s2
Explanation: Atomic number of Au is 79, its electronic configuration is1s22s22p63s23p63d104s24p64d105s25p64f145d106s1(The electronic configuration of…
Correct answer: [Xe]4f14, 5d10, 6s1- A. A
- B. B
- C. C
- D. D
Explanation: Energy gained by the electron when accelerated through a potential of V volts is E=eV This energy is completely converted to kinetic…
Correct answer: A- A. Na
- B. Boron
- C. K
- D. Ca
Explanation: A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from the emission or absorption of…
Correct answer: Na- A. excited state
- B. ground state
- C. cationic form
- D. anionic from
Explanation: The given electronic configuration is ground state for chromium. Hence, (B) is the correct answer.
Correct answer: ground state- A. Cr3+, Fe3+
- B. Fe3+, Mn2+
- C. Fe3+, Co3+
- D. Se3+, Cr3+
Explanation: Fe³+and Mn²+ have same electronic configuration. Hence (B) is the correct answer.
Correct answer: Fe3+, Mn2+- A. AgNO3 plate
- B. AgC1 plate
- C. ZnO
- D. ZnS
Explanation: Positive rays produce flashes upon ZnS plate.
Correct answer: ZnS- A. n = 3, / = 0
- B. n =3, / = 1
- C. n = 2, /.= 1
- D. n = 2, / = 3
Explanation: For 3p subshell quantum number values are n = 3, ℓ = 1.
Correct answer: n =3, / = 1- A. 3-d is full filled
- B. 3-d is half filled
- C. 1 electron in 4s-orbitals
- D. 8 electrons in s-orbitals
Explanation: So, when we talk about the electronic configuration of copper (Cu) and chromium (Cr), we look at the arrangement of electrons in their…
Correct answer: 1 electron in 4s-orbitals- A. Aufbau principle
- B. Hund's rule
- C. Paull's exclusion principle
- D. n+I rule
Explanation: Aufbau principle best explains the valency of an element. The Aufbau principle states that electrons fill orbitals in order of increasing…
Correct answer: Aufbau principle- A. 6.626 x 10^-34 KJs
- B. 6.262 x 10^-34 Js
- 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