Free Composition of Atomic Nuclei MCQs with Answers
100 Composition of Atomic Nuclei MCQs from Physics, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Atomic nuclei contain positively charged protons and electrically neutral neutrons, collectively called nucleons. Questions use atomic number, mass number and nuclear notation to identify isotopes, isobars and isotones, and may connect nuclear composition with nuclear charge, mass defect, binding energy and the stability of the nucleus.
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100 questions · page 3 of 5
- A. C12
- B. C14
- C. C10
- D. None of these
Explanation: Carbon-14, the longest-lived radioactive isotope of carbon, whose decay allows the accurate dating of archaeological artifacts.
Correct answer: C14- A. 194
- B. 202
- C. 200
- D. None of these
Explanation: When a nucleus emits an alpha particle, these changes happen: the mass number decreases by 4, and the atomic number decreases by 2.
Correct answer: 194- A. R=r0A^-1/3
- B. R= r0A"^/3
- C. R= roA^3
- D. None of these
Explanation: Most nuclei are approximately spherical. The average radius of a nucleus with A nucleons is R = R0A1/3, where R0 = 1.2*1015 m.
Correct answer: R= r0A"^/3- A. Protons
- B. Electron
- C. Neutrons
- D. All of them
Explanation: Option C is correct since the isotopes are defined as elements having the same proton number but different nucleon numbers.
Correct answer: Neutrons- A. Atomic number
- B. Proton number
- C. Different mass number
- D. All of these
Explanation: Option D is correct since isotopes have the same atomic number, same proton number, and different mass numbers.Option A is incorrect as it…
Correct answer: All of these- A. Proton
- B. Neutron
- C. Electron
- D. Atom
Explanation: Isotopes of an element have different numbers of neutrons. The number of protons in an atom determines what element it is, but the number…
Correct answer: Neutron- A. 04.8 MeV
- B. 13.6 MeV
- C. 23.6 MeV
- D. 25.8 MeV
- E. 26.2 MeV
Explanation: The energy released when two deuterons fuse to form a helium nucleus can be calculated using the formula:1H² + H² →2 He* + Qwhere Q is the…
Correct answer: 23.6 MeV- A. Proton: 1u + 1d, Neutron: 2u + 1d
- B. Proton: 2u + 2d, Neutron: 2u + 1d
- C. Proton: 2u + 1d, Neutron: 1u + 2d
- D. Proton: 1/3 u + 2/3 d, Neutron: 2/3 u + 1/3 d
- E. Proton: 1/3 u + 1/3 d, Neutron: 2/3 u + 2/3 d
Explanation: Protons and neutrons are composed of quarks. Protons contain two up quarks and one down quark, while neutrons contain one up quark and two…
Correct answer: Proton: 2u + 1d, Neutron: 1u + 2d- A. Nucleons
- B. Neutrons
- C. Protons
- D. Neutrons and protons
Explanation: Isotopes are the elements having same atomic number or charge number but different mass number.
Correct answer: Protons- A. Option A
- B. Option B
- C. Option C
- D. Option D
Explanation: Number of neutrons= Mass number - charge number Number of neutrons = 235 - 92 = 143 Number of protons = number of electrons = 92 So, the…
Correct answer: Option B- A. 11 electrons, 11 protons and 13 neutrons
- B. 12 protons and 12 neutrons
- C. 11 electrons, 13 protons and 11 neutrons
- D. 11 protons and 13 electrons
Explanation: Atomic mass 24 is of Magnessium. It has 12 atomic charge , which means 12 protons and atomic mass 24.
Correct answer: 12 protons and 12 neutrons- A. Two extra protons and two extra electrons
- B. Two extra neutrons and no extra electrons
- C. Two extra protons but no extra electrons
- D. Two extra neutrons and two extra electrons
Explanation: Isotopes have same number of electrons and protons but different number of neutrons due to different mass number.
Correct answer: Two extra neutrons and no extra electrons- A. 126 C and 146 C
- B. 614 C and 714N
- C. 42 He and 31H
- D. Both A and C
Explanation: Isobars have different atomic number but same atomic mass. This option clearly shows elements having same atomic mass but different atomic…
Correct answer: 614 C and 714N- A. 10- 12m
- B. 10-10m
- C. 10-11m
- D. 10-14m
Explanation: Diameter of nucleus is approximately 10-14m. This is a fact to be memorized.
Correct answer: 10-14m- A. Option A
- B. Option B
- C. Option C
- D. Option D
Explanation: Option A is correct because alpha particles have high ionization power but low penetrating power which represents P.
Correct answer: Option A- A. 14
- B. 10
- C. 12
- D. 16
Explanation: On the left-hand side of the reaction, we have the sum of the mass numbers of the reactants: Mass number before the reaction = 9 (mass…
Correct answer: 12- A. Z = N
- B. Z < N
- C. Z > N
- D. Z + N = A
Explanation: The explanation of this is given below: In heavy elements, such as those with higher atomic numbers (larger Z values), the balance between…
Correct answer: Z < N- A. N = A - Z:
- B. N = A + Z:
- C. N = A x Z:
- D. N = ½ A + Z
Explanation: The number of neutrons is equal to the mass number (A) minus the atomic number (Z)In summary, the correct option is **a.
Correct answer: N = A - Z:- A. Photons
- B. Leptons
- C. Bosons
- D. Hadrons
Explanation: The particles that experience the strong nuclear force are hadrons. The strong nuclear force is a short-range but extremely powerful force…
Correct answer: Hadrons- A. 1.66 x 10^-27kg
- B. 602 x 10^-27 Kg
- C. 6.02 x 10^-23Kg
- D. 2.67 x 10^-23kg
Explanation: The mass equivalent of 931 MeV of energy can be calculated using Einstein's mass-energy equivalence formula E = mc2 where ( E ) is energy…
Correct answer: 1.66 x 10^-27kg