Two samples each of substance A and B are kept in an open container and air tight container . Sample A in first container became sticky and in second container remained as such. Sample B in both the containers remained without any change. Comment on the above observation.

Two samples each of substance A and B are kept in an open container an

1.	Two samples each of substance A and B are kept in an open container and air tight container . Sample A in first container became sticky and in second container remained as such. Sample B in both the containers remained without any change. Comment on the above observation.
Answer» Solution :SUBSTANCE A in open container becomes sticky and that means it is a deliquescent substance and absorbs sufficient MOISTURE in an open container . In an AIR tight container, it absorbs little moisture but again loses some moisture for maintaining equilbrim vapour pressure. THEREFORE, it does not become sticky EVEN in opencontainer. The fact that it remained without any change in open container indicated that it is neither efflorescent nor deliquescent . It may be a hygroscopic salt or may not absorb moisture at all.