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Model Paper 10 — Chemistry STD 11 Science — Question

Rajasthan BoardEnglish MediumSTD 11 ScienceChemistryModel Paper 101 Mark
Question
Assertion (A): The nuclear isomers are the atoms with the same atomic number and same mass number, but with different radioactive properties.
Reason (R): The nucleus in the excited state will evidently have a different half-life as compared to that in the ground state.
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Answer

(a) Both A and R are true and R is the correct explanation of A .
Explanation: The nuclear isomerism in the nuclei of the same mass number and same atomic number arises due to different radioactive properties. The reason for nuclear isomerism is the different energy states of two isomeric nuclei. One may be in the ground state and the other in an excited state. The nucleus in the excited state will have a different half-life.

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