Related InterviewSolutions

• When a nucleus with atomic number Z and mass number A undergoes a radioactive decay process, (a) both Z and A will decrease, if the process is α decay (b) Z will decrease but A will not change, if the process is β+ decay (c) Z will increase but A will not change, if the process is β- decay (d) Z and A will remain unchanged, if the process is γ decay
• Let ν1 be the frequency of the series limit of the Lyman series, ν2 be the frequency of the first line of the Lyman series, and ν3 be the frequency of the series limit of the Balmer series. (a) ν1 - ν2 = ν3 (b) ν2 - ν1 = ν3 (c) ν3 = 1/2 (ν1 + ν2) (d) ν1 + ν2 = ν3
• When a hydrogen atom emits a photon of energy 12.1 eV, its orbital angular momentum changes by (a) 1.05 x 10-34 J s (b) 2.11 x 10-34 J s (c) 3.16 x 10-34 J s (d) 4.22 x 10-34 J s
• A photon of energy 10.2 eV corresponds to light of wavelength λ0. Due to an electron transition from n = 2 to n = 1 in a hydrogen atom, light of wavelength λ is emitted. If we take into account the recoil of the atom when the photon is emitted,(a) λ > λ0 (b) λ > λ0 (c) λ > λ0 (d) the data is not sufficient to reach a conclusion
• Which of the following pairs constitute very similar radiations? (a) Hard ultraviolet rays and soft X-rays (b) Soft ultraviolet rays and hard X-rays (c) Very hard X-rays and low-frequency γ-rays (d) Soft X-rays and γ-rays
• An orbital electron in the ground state of hydrogen has an angular momentum L1, and an orbital electron in the first orbit in the ground state of lithium has an angular momentum L2. (a) L1 = L2 (b) L1 = 3L2 (c) L2 = 3L1 (d) L2 = 9L1
• A sample of radioactive material is used to provide desired doses of radiation for medical purposes. The total time for which the sample can be used will depend (a) only on the number of times radiation is drawn from it (b) only on the intensity of doses drawn from it (c) on both (a) and (b) (d) neither on (a) nor on (b)
• Which of the following assertions are correct? (a) A neutron can decay to a proton only inside a nucleus. (b) A proton can change to a neutron only inside a nucleus. (c) An isolated neutron can change into a proton. (d) An isolated proton can change into a neutron.
• Two identical nuclei A and B of the same radioactive element undergo β decay. A emits a β-particle and changes to A'. B emits a β-particle and then a γ-ray photon immediately afterwards, and changes to B'. (a) A' and B' have the same atomic number and mass number. (b) A' and B' have the same atomic number but different mass numbers (c) A' and B' have different atomic numbers but the same mass number. (d) A' and B' are isotopes.
• A and B are isotopes. B and C are isobars. All three are radioactive. (a) A, B and C must belong to the same element. (b) A, B and C may belong to the same element. (c) It is possible that A will change to B through a radioactive decay process. (d) It is possible that B will change to C through a radioactive decay process.