Osmosis and Diffusion

June is in 5^th grade and she is keen on being an astute student.  She understands that diffusion is the movement of molecules from a region of high concentration to a region of low concentration across a diffusion gradient. However she is keen on applying this knowledge in everyday life. As complex as this appears, this process is well exemplified when she dilutes juice in water. It’s impossible to consume concentrated juice and hence the need for dilution. Initially, the juice molecules will be concentrated at one area of the glass but with time, they will gradually move i.e. diffuse until they are evenly distributed in the water. Osmosis is similar to diffusion but differs on two principles. First, osmosis refers to the movement of water molecules from a region of high concentration to a region of low concentration. Secondly, osmosis takes place across a semi permeable membrane.

The process of diffusion occurs in everyday life and June is quite familiar these experiences. Most noteworthy, is a common but rather embarrassing process, farting. As much as this is discomforting, in this context June can appreciate it as a good example of diffusion. The bad odor is released by the ‘culprit’ and the odor molecules move around the room/atmosphere until they are evenly distributed.  Eventually, these molecules move far apart and hence, the odor can no longer be smelt. Initially, the concentrated odor molecules were offensive before diffusion. On a brighter note, diffusion occurs when she smells baking cookies. Being the only child, her mom spoils her to bits. June’s mom loves to bake cookies for her princess.  In this case, the sweet aroma from the oven diffuses into the atmosphere and that is how June’s senses become scintillated before she devours her cookies.

Osmosis is another common process. For instance if water spills in the kitchen, mommy is bound to grab a mop. The duster/mop absorbs the water as the water molecules move from a region of high concentration (on the floor)   to a region of low concentration (mop/duster). Osmosis occurs when mommy soaks beans. She does this to eliminate the flatulence factors that cause discomfort and also to reduce the cooking time. However, these beans swell after absorbing water via the process of osmosis. June’s understanding for diffusion and osmosis is greater as she has seen the relevance of learnt knowledge in everyday life.