# The species which contain an odd number of valence electrons and are paramagnetic are

$(a)\;\text{(i),(ii) and (iii) } \\ (b)\;\text{(i),(ii) and (iv)} \\(c)\;\text{(ii),(iii) and (iv) } \\(d)\;\text{(i),(iii) and (iv)}$

$NO$ (5+6=11 valence electrons)
$NO_2$ (5+12=17 valence electrons)
$ClO_2$ (7+12=19 valence electrons)
All molecules have odd electrons and are paramagnetic .
Hence a is the correct answer.
answered Apr 2, 2014 by