Chapter 12: Atoms Assertion Reason
These questions of two statements each, printed as Assertion and Reason. While answering these Questions you are required to choose any one of the following four responses.
(A) If both Assertion & Reason are true & the Reason is a correct explanation of the Assertion.
(B) If both Assertion and Reason are true but Reason is not a correct explanation of the Assertion.
(C) If Assertion is true but the Reason is false.
(D) If Assertion & Reason both are false.
Assertion-Reason Questions
- Assertion (A): Electrons in an atom revolve around the nucleus in fixed orbits.
Reason (R): The centripetal force required by the electrons to stay in their orbits is provided by the electrostatic attraction between the positively charged nucleus and the negatively charged electrons.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The energy of an electron in an atom is quantized.
Reason (R): Electrons can only occupy certain allowed energy levels within the atom.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): In the hydrogen atom, the electron revolves in circular orbits.
Reason (R): The centripetal force is provided by the electrostatic attraction between the proton and the electron.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The frequency of radiation emitted or absorbed by an atom is related to the difference in energy between two energy levels.
Reason (R): The energy of the photon emitted or absorbed is equal to the difference in energy between the two levels.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The ground state of an atom is its lowest energy state.
Reason (R): In the ground state, the electron occupies the closest possible orbit to the nucleus.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The Bohr model of the atom explains the line spectra of hydrogen.
Reason (R): The energy levels of the electron in the hydrogen atom are quantized, leading to discrete spectral lines.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The angular momentum of an electron in a Bohr orbit is quantized.
Reason (R): The angular momentum of the electron is an integral multiple of h/2π.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The emission spectrum of an element is characteristic of the element.
Reason (R): The energy levels of electrons in an atom are unique to each element.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The ionization energy of an atom is the energy required to remove an electron from the atom in its ground state.
Reason (R): Ionization energy is a measure of the binding energy of the electron in the ground state.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The wavelength of light emitted in an electronic transition is inversely proportional to the energy difference between the initial and final states.
Reason (R): The energy of a photon is inversely proportional to its wavelength.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The energy levels in an atom are quantized due to the wave nature of electrons.
Reason (R): Electrons exhibit both particle and wave properties, leading to standing wave patterns in the atom.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The Zeeman effect is the splitting of spectral lines in the presence of a magnetic field.
Reason (R): The magnetic field interacts with the magnetic moments of the electrons, causing energy level shifts.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The Heisenberg uncertainty principle places a limit on the precision with which the position and momentum of an electron can be simultaneously known.
Reason (R): The act of measuring one quantity disturbs the other.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The probability density of finding an electron in an atom is given by the square of the wave function.
Reason (R): The wave function describes the quantum state of the electron in the atom.
Answer: Both A and R are true and R is the correct explanation of A.Chapter 11: Dual Nature of Radiation and Matter Assertion Reason
Chapter 13: Nuclei Assertion Reason
Class 12 Physics Notes