खालीलपैकी कोणते वायू रंगहीन आणि गंधहीन नाही? A. नाइट्रोजन B. क्लोरीन C. हायड्रोजन D. ऑक्सिजन

Nitrogen, hydrogen and oxygen are all colourless and odourless gases. Chlorine is the exception: it is a greenish-yellow gas with a sharp, pungent, choking smell (the smell noticed near bleach or swimming pools). So chlorine is the gas that is not colourless and odourless.