When object is immersed in water the volume of the water is found to increase due to upthrust...But this is not true when the object is salt. If you pour a handful of salt into a glass of water, the water level will go down.If you think water will over flow when you add handful salt dust into a full glass of water, it’s wrong. Really water level goes down. Common Salt made of NaCl. When we added salt in to water, NaCl separated in to Na+ and Cl- ions. After this separation water molecules began to bond with those ions. Because of these inter molecular bonding volume of water decrease.
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