NEET Solved Paper 2014 Question 19
Question: $ B{e^{2+}} $ is isoelectronic with which of the following ions? [AIPMT 2014]
Options:
A) $ {H^{+}} $
B) $ L{i^{+}} $
C) $ N{a^{+}} $
D) $ M{g^{2+}} $
Show Answer
Answer:
Correct Answer: B
Solution:
Isoelectronic species contain same number of electrons.
$ B{e^{2+}} $ contains 2 electrons. Among the given options,
only $ L{i^{2+}} $ contains 2 electrons and therefore, it is isoelectronic with $ B{e^{2+}} $ .
$ {H^{+}}\to $ no electron; $ N{a^{+}}\to 10{e^{-}} $ $ L{i^{+}}\to 2{e^{-}};M{g^{2+}}\to 10{e^{-}} $
Hence, $ B{e^{2+}} $ is isoelectronic with $ L{i^{+}} $ .
