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 23 of 47
- A. N2O
- B. CO2
- C. He
- D. H2
Explanation: Out of these options, only helium is a monoatomic molecule i.e. having a single atom.
Correct answer: He- A. Nucleus of the atoms
- B. Atomic number
- C. Number of atoms
- D. None of the above
Explanation: From the explanation below (PTB I, p. 141), the most suitable choice is "atomic number" because higher atomic number means a greater…
Correct answer: Atomic number- A. None of these
- B. Influencing the electron
- C. that does not influence the electronegativity
- D. Influencing the ionization energies
Explanation: The atomic radius of an atom is a factor influencing ionization energies.
Correct answer: Influencing the ionization energies- A. One
- B. Three
- C. Five
- D. Zero
Explanation: Since S has no orientation in other axes therefore the magnetic quantum number for S is always zero.
Correct answer: Zero- A. Einstein
- B. Maxwell
- C. Newton
- D. Planck
Explanation: The Planck constant (Planck's constant) tells us what would be the change in the energy of a photon when the frequency of its…
Correct answer: Planck- A. 1/1836
- B. 1836
- C. 2
- D. 1.6
Explanation: Protons have a rest mass of 1.67262 × 10−27 kg which is 1,836 times the mass of an electron (9.1×10-31 kg).
Correct answer: 1836- A. De-excitation
- B. Ground state
- C. Excitation
- D. Excited state
Explanation: When an electron absorbs energy and jumps from a lower energy level to a higher energy level, it is known as excitation.
Correct answer: Excitation- A. 1
- B. 3
- C. 0
- D. 2
Explanation: The Azimuthal quantum number describes the subshells and the magnitude of the orbital angular momentum.
Correct answer: 1- A. Same spin
- B. cannot have same values of all four quantum numbers
- C. Opposite spin
- D. Same value for spin quantum number
Explanation: Pauli's exclusion principle states that no two electrons in a single atom can have the same values for all four quantum numbers.
Correct answer: cannot have same values of all four quantum numbers- A. 7,8,9
- B. 7,7,7
- C. 14,14,14
- D. 14,14,15
Explanation: The most common isotope of Nitrogen has atomic number 7 and mass number 14.
Correct answer: 14,14,14- A. 2(l+l)
- B. l+l
- C. n+l
- D. 2(n+l)
Explanation: The n+l rule is used to arrange subshells and orbitals in order of increasing energy where n is the principal quantum number and l is the…
Correct answer: n+l- A. Bohr's
- B. Rutherford's
- C. Dalton's
- D. Cannizzaro's
Explanation: OPTION A: Bohr's is incorrect as Niels Bohr's theory is related to the electronic structure of atoms, not the fundamental nature of…
Correct answer: Dalton's- A. +6.8 eV
- B. +20.4 eV
- C. - 6.8 eV
- D. +3.4 eV
Explanation: This is the following solution:The energy of an electron in its nth orbit = -13.6/n2.
Correct answer: - 6.8 eV- A. Dequantized
- B. Quantized
- C. Emitted
- D. Changes always
Explanation: Option A: This option suggests that the electron's momentum is not restricted to specific values and can take on any value continuously.
Correct answer: Quantized- A. de-Broglie
- B. Mosley
- C. Heisenberg
- D. Neil Bohr
Explanation: De Broglie's statement, also known as the De Broglie hypothesis, states that every object or particle in motion, regardless of its mass…
Correct answer: Heisenberg- A. 1/n
- B. n2
- C. 1/n2
- D. N
Explanation: According to Bohr's model of the atom, electrons occupy certain energy levels or orbits around the nucleus.
Correct answer: n2- A. Lower
- B. Greater
- C. Higher
- D. Moderate
Explanation: The greater the value of the principal quantum number 'n', the greater the distance of an electron from the nucleus will be.The principal…
Correct answer: Greater- A. First two
- B. First three
- C. In all axis
- D. None of these
Explanation: The lobes of d-orbitals lie between the first three axes. The d-orbitals are located in the third shell of an atom, and they have a…
Correct answer: First three- A. Low-speed neutrons
- B. High-speed neutrons
- C. Low-speed electrons
- D. High-speed electrons
Explanation: In the Discharge Tube Experiment, high-speed electrons transition from the metal of the cathode and go towards the anode.
Correct answer: High-speed electrons- A. To n
- B. To s
- C. To n-1.
- D. To s-1.
Explanation: "n" is the Principal Quantum Number, "s" is the Spin Quantum Number, and "l" is Azimuthal Quantum Number.
Correct answer: To n-1.