NEET Chemistry Structure of Atom / परमाणु संरचना NEET PYQ-Structure of Atom

Which of the following is iso-electronic?                                                                              [AIPMT 2002]

A)       \[C{{O}_{2}},\text{ }N{{O}_{2}}\]

B)      \[NO_{2}^{-},\,C{{O}_{2}}\]

C) \[C{{N}^{-}},\text{ }CO\]

D)      \[S{{O}_{2}},\,C{{O}_{2}}\]

Correct Answer: C

Solution :

\[C{{N}^{-}}\] and CO are iso-electronic because they have equal number of electrons.

In \[C{{N}^{-}}\] the no. of electrons \[=~6+7+1=14\]

In CO the no. of electrons \[=\text{ }6+8=14\]