Diffusion and Osmosis

Diffusion is the movement of particles through a concentration gradient from a high concentration to a low concentration. Diffusion is a passive process which means it doesn't need energy. Diffusion can happen in liquid and gas but not in solid because the particles in solid materials are tightly packed together. Diffusion in gas happens all the time in our daily life for example there is a sock 1 meter away from us but we can smell the socks, this happens because of diffusion.

Diffusion also happens in liquid, to prove that we have conducted an experiment. First, we prepared a container with water and food dye. We put in several drops of food dye and in a few minutes without mixing it the food dye becomes evenly spread out meaning diffusion happened. In this experiment, first the spot where we drop food dye has a high concentration than the other spots without food dye because of the difference of concentration the particles of the food dye will move and diffusion happens.

The next topic we are going to discuss is osmosis. Osmosis is a special case of diffusion where water moves from a high concentration to a low concentration through a permeable membrane. Osmosis is a special case of diffusion meaning that it is also a passive process which doesn't need energy. To understand more about this concept we have conducted an experiment. First, we prepared two eggs and put it in two containers. Next, we need to expose the permeable membrane by putting it in vinegar for 3 days.

Like the picture, the eggs will become like a rubbery egg and it will change in color and increase in size. After doing this, we put the egg into a hypertonic solution and a hypotonic solution. A hypertonic solution is a solution that has more solute than water molecules while a hypotonic solution is a solution with more water molecules than solute. In this experiment, we use syrup as the hypertonic solution and we use water for the hypotonic solution then we leave it for around 8 hours. The result is that the egg in the hypertonic solution shrink in size while the egg in the hypotonic solution increase in size. 

This proves that osmosis happens. When we put it in a hypotonic solution, where there are more water molecules than solute meaning that the water concentration in the solution is higher than the water concentration of the egg. So, the water will move from the solution to the egg making the egg increase in size. The opposite happens when the egg is put into a hypertonic solution, the egg has a higher water concentration than the solution so the water leaves the egg causing it to shrink. 

With these two experiments, we have proven diffusion and osmosis and how the molecules move. Hope this is useful and to know more about the importance of osmosis and diffusion, wait for my next post. Thank you for reading.