7. Out of elements $\frac{34}{17}X and \frac{40}{18}Y$, which is chemically more reactive and why?
11. Why do isotopes show similar chemical properties?
 

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https://www.meritnation.com/ask-answer/question/do-isotopes-have-same-chemical-properties-why/the-language-of-chemistry/11573341">https://www.meritnation.com/ask-answer/question/out-of-the-elements-1734cl-and-1840ar-which-is-chemically-m/science/8836301                                                                                                                                   https://www.meritnation.com/ask-answer/question/do-isotopes-have-same-chemical-properties-why/the-language-of-chemistry/11573341