Question

why does water potential decrease when placed in high concentration?

Answer 1

If the potato is allowed to dehydrate by sitting out in the open air the water potential would decrease (be more negative) because the concentration of solutes within the cells would increase as potato cells dehydrate. Therefore, theosmotic pressure and water potential bothdecrease.

Answer 2

Since water has a tendency to move toward lower energy levels, water will want to travel toward the zone of higher solute concentrations. Although, liquid water will only move in response to such differences in osmotic potential if a semipermeable membrane exists between the zones of highand low osmotic potential.