What is osmosis?

Osmosis is a process whereby molecules of a higher concentration go to an area of a lower concentration. For instance, if you have a bag made of porous material, such as cellulose, you fill it with orange juice and place it in a bowl of distilled water, the orange juice will start to 'leak' into the water. Therefore, you will see a colour change of the water over time from clear to orange. The high concentration of sugars and other molecules of the orange juice go to an area of a lower concentration of ions and sugars, into the water.