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Given below are two statements, one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : The density of the copper (^{64}_{29}Cu) nucleus is greater than that of the carbon (^{12}_{6}C) nucleus. Reason (R) : The nucleus of mass number A has a radius proportional to A^{1/3}. In the light of the above statements, choose the most appropriate answer from the options given below. (1) Both (A) and (R) are correct and (R) is the correct explanation of (A) (2) (A) is not correct but (R) is correct (3) Both (A) and (R) are correct and (R) is not the correct explanation of (A) (4) (A) is correct but (R) is not correct
- Both (A) and (R) are correct and (R) is the correct explanation of (A)
- (A) is not correct but (R) is correct
- Both (A) and (R) are correct and (R) is not the correct explanation of (A)
- (A) is correct but (R) is not correct
Correct answer: (A) is not correct but (R) is correct
Solution
The assertion is incorrect because the density of nuclei does not significantly vary between different elements like copper and carbon; they are generally similar. However, the reason is correct as it accurately describes the relationship between the mass number and the radius of a nucleus.
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