In this experimental set up 3 potatoes 2 raw and 1 cooked are used. All 3 have a cavity and are placed in a tray of water. One of the raw potatoes and the cooked one have salt filled in their cavities. The cavity in the other raw potato is left empty. When the potatoes are observed some time later, the salt in the raw potato is dissolved in water, while the salt in the cooked potato is still in the solid form with no water. The 3rd potato is without water. What happened here is like this. Because of osmosis, the cells of the potato surrounding the salt filled cavity gave out water into the cavity. This water is drawn from the water lying in the tray. The cooked potato cells are dead and so do not undergo osmosis. So no water is drawn in and the salt remains dry. In the case of the 3rd potato, as there is no salt, the cells do not develop sufficient osmotic pressure to draw in water..