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If you've ever wondered how particles move around, diffusion is the answer. Basically, diffusion happens when particles move from a place where there are a lot of them to a place where there aren't as many. This can happen in liquids and gases because particles move around randomly. It's a really important concept in science, and it can help us understand a lot about how things work in the world around us. So next time you see something spreading out, think about how diffusion might be playing a role!

Diffusion across cell membranes?

Cell membranes are like superheroes! They keep cells together and let important stuff go in and out. One way this happens is through diffusion, which is when tiny dissolved particles move through the membrane. But only really small things like water, oxygen, glucose, and amino acids can get through. Big things like proteins and starches can't pass. Just like how air molecules spread out, particles move through the membrane from where there are lots of them to where there are fewer. They move randomly, but if there's a lot more on one side of the membrane, they'll go that way more often.

What are some examples of diffusion?

Imagine someone opening a bottle of perfume in a crowded room. The perfume is strongest in the bottle and weakest on the far edges of the room. As the perfume spreads, more people will be able to smell it. This is a great example of diffusion!

Diffusion is also what helps us breathe. When we breathe in, our lungs take in oxygen, which is needed for our cells to work properly. Oxygen is less concentrated inside our bodies, so it moves into our cells. At the same time, we breathe out carbon dioxide, which is produced inside our cells. Carbon dioxide is more concentrated inside our bodies, so it moves out. Both of these gases move across the membrane in our lungs in a process known as diffusion. It's pretty amazing how our bodies use diffusion to keep us alive!

What factors affect the rate of diffusion?

1.       Diffusion occurs at various rates based on a number of factors:

2.       Concentration gradient: The diffusion is accelerated by a greater concentration gradient. The diffusion rate slows as the distribution of the chemicals gets closer to equilibrium.

3.       Solvent density: Diffusion rates decrease with increasing solvent density. This is due to the slower motion of molecules in a denser liquid. On the other hand, diffusion happens more quickly the less dense the solvent is.

4.       Molecule weight: Larger molecules diffuse more slowly because they move more slowly. On the other hand, lighter molecules diffuse more quickly because they travel more quickly.

5.       Temperature: Higher temperatures enhance thermal energy, which causes the molecules to move more quickly and raises the rate of diffusion. Lower temperatures have the exact opposite effect.

Osmosis vs diffusion: what are their similarities and differences?

When two solutions with different concentrations are brought together, particles move from areas of high concentration to areas of low concentration until they are in equilibrium. This process is called passive transport and includes two processes: osmosis and diffusion.

Osmosis and diffusion are different. During osmosis, only solvent molecules (usually water) pass through the membrane to balance the concentration of solute molecules on either side of the semi-permeable membrane. However, during diffusion, both solvent and solute molecules move across the membrane. In a solution, the substance that dissolves is the solvent, while the substance that is dissolved is the solute. Osmosis is a type of diffusion that occurs when solute molecules cannot pass through a barrier on their own. Instead, water molecules move across the membrane to the side with a higher concentration of solute particles until they reach equilibrium. This process is essential for many biological processes!


What is diffusion?

Diffusion is a process where molecules distribute themselves to any available space.  

Does diffusion require energy?

No, diffusion is a form of passive transport thus requires no energy.

Is diffusion active or passive?

Diffusion is a form of passive transport.

What is the difference between osmosis and diffusion?

A key distinction is that in diffusion, both solvent and solute molecules move, but in osmosis, only solvent molecules move across the membrane.

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