Solution: The tendency of water to migrate from one location to another due to osmosis, gravity, and mechanical pressure is known as water potential. In other words, it is the difference between the free energy or chemical potential of water in a system per unit molal volume compared to pure water at the same pressure and temperature. It can be calculated in pressure units. Pure water is characterised as having a 0 water potential at standard temperature and pressure. Potential decreases as solutes are added to water, while potential increases as pressure rises.

Water potential is affected by the following factors:

• Solute potential
• Pressure potential
• Matric potential
• Pressure
• Temperature
• Water gain/loss