Water Potential
The tendency of a solution to donate water is termed its water potential. The more likely a solution is to give up water the higher its water potential, but the scale is a nagative one, and the highest water potential value possible is 0 (zero) as possessed by pure water.
Adding a solute like salt or sugar to pure water progressively reduces its water potential, making it more negative.
Adding a cell to a solution that has lower water potential than the cell causes water to move out of the cell.
Adding a cell to a solution that has a higher water potential than the cell causes water to move into the cell.

The picture below illustrates how water moves to the area with the lowest (most negative) water potential

Plasmolysis
A plant cell in a strong salt solution will donate water until its cell membrane pulls away from the cell wall. This is plasmolysis. When 50% of the cells in sample being viewed are found to be showing signs of plasmolysis, then incipient plasmolysis is said to have occurred.

Osmosis Questions
1. Which will happen to each cell because of the water potential of the sorrounding solution? (I have not included the answer to this- email me !)

2. In which direction(s?) will water move in the following arrangement of cells?
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Try your osmosis knowledge with this additional question