Why does a raw egg get lighter when put in saltwater?

A raw egg gets lighter when placed in saltwater due to the process of osmosis. The saltwater has a higher concentration of solutes compared to the liquid inside the egg, causing water to move out of the egg through the semi-permeable shell. This loss of water from the egg makes it less dense and gives the appearance of being lighter in the denser saltwater. Consequently, the egg may also float in saltwater, as its buoyancy increases.