Find the odd one out among the following sets. Give reasons.
(a) Nitrogen, fluorine, oxygen, hydrogen, ozone.
(b) CaO, NaCl, Co, FeS, `KNO_(3)`
(c ) Se, K, Cu, Pb, SI.
(d) Bromine, iodine, carbon, sulphur, silicon.

Explanation

(a) Ozone (b) Co
(c ) Sl
(d) Bromine
(a) Ozone is a triatomic molecule while others are diatomic molecules.
(b) Co is the symbol for cobalt which is an element while others are compounds.
(c ) Sl is not the symbol for any element while others are symbols for the respective elements.
(d) Bromine is liquid non-metal and others are solids.