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Question
Heavy stable nucle have more neutrons than protons. This is because of the fact that ______.
Options
neutrons are heavier than protons.
electrostatic force between protons are repulsive.
neutrons decay into protons through beta decay.
nuclear forces between neutrons are weaker than that between protons.
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Solution
Heavy stable nucle have more neutrons than protons. This is because of the fact that electrostatic force between protons are repulsive.
Explanation:
Neutron-proton ratio `(N/2 "ratio")`: The chemical properties of an atom are governed entirely by the number of protons (Z) in the nucleus, the Stability of an. atom appears to depend on both the number of protons and the number of neutrons.
- For lighter nuclei, the greatest stability is achieved when the number of protons and neutrons are approximately equal (N = Z), ie. `N/Z` = 1
- Heavy nuclei are stable only when they have more neutrons than protons. Thus heavy nuclei are neutron-rich compared to lighter nuclei (for heavy nuclei, more the protons in the nucleus, the greater the electrical repulsive force between them. Therefore more neutrons are added to provide the strong attractive forces necessary to keep the nucleus stable.)
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