Classification Of Elements And Periodicity In Properties Ques 298
Question: The correct order of ionic size of $ {{N}^{3-}},N{{a}^{+}},N{{a}^{+}},{{O}^{2-}},{{F}^{-}},M{{g}^{2+}} $ will be
Options:
A) $ {{O}^{2-}}<N{{a}^{+}}<{{F}^{-}}<{{N}^{3-}}<M{{g}^{2+}} $
B) $ M{{g}^{2+}}N{{a}^{+}}<{{F}^{-}}<{{O}^{2-}}<{{N}^{3-}} $
C) $ {{F}^{-}}<{{N}^{3-}}<{{O}^{2-}}<M{{g}^{2+}}<N{{a}^{+}} $
D) $ {{F}^{-}}<M{{g}^{2+}}<{{O}^{2-}}<N{{a}^{+}}<{{N}^{3-}} $
Show Answer
Answer:
Correct Answer: B
Solution:
[b] Idea This problem can be solved by using the concept variation of atomic size along period. Which can be solved by using the skill of nuclear charge. All given species are is electronic having $ 10{{e}^{\Theta }}s $ but more negative charge on atom higher will be radius and more +ve charge smaller will be radius hence. $ M{{g}^{2+}}<N{{a}^{+}}<{{F}^{-}}<{{O}^{2-}}<{{N}^{3-}} $ TEST Edge: Problems relating trend in atomic properties such as ionisation enthalpy, electron gain enthalpy are asked frequently. So, students are advised to study in depth about their meaning, periodic variation and relation between them.
