InterviewSolution
Saved Bookmarks
InterviewSolution
| 1. |
Assertion : A nuclear binding energy per nucleon is in the order `._(4)^(9)Be gt ._(3)^(7)Li gt ._(2)^(4)He` Reason : Binding energy per nucleon increases linearly with difference in number of neutrons and protons.A. If both assertion and reason are true and the reason is the correct explanation of the assertionB. If both assertion and reason are true but reason is not the correct explanantion of the assertionC. If assertion is true but reason is falseD. If the assertion and reason both are false |
|
Answer» Correct Answer - D Binding energy per nucleon of `._(3)Li^(7)` (5.38 MeV) is lesser than `._(2)He^(4)` (7.08 MeV) as helium is found to be more stable than Li. As the atomic mass number increases, the binding energy per nucleon decreases. As the atomic number and the atomic mass number increase, the repulsive electrostatic forces with in the nucleus increase due to the greater number of protons in the heavy elements. To over come this increased repulsion, the proportion of neutrons in the nucleus must increase to maintain stability. This increase in the neutron to proton ratio only partially compensates for the growing proton-proton repulsive force in the heavier, naturally occurring elements. |
|