Osmotic Pressure Dialysis Tubing

Summary

This educational video demonstrates the concept of osmosis using dialysis tubing, a semi-permeable membrane. The experiment involves placing molasses inside the tubing and submerging it in water. After two hours, the molasses in the tubing with water becomes less viscous, indicating that water molecules have passed through the membrane, diluting the molasses. This change is attributed to osmotic pressure, showcasing the principle that small molecules can pass through a semi-permeable barrier while larger ones cannot.

Takeaways

• 🧪 Dialysis tubing is a semi-permeable membrane used to demonstrate osmosis.
• 🌀 Large molecules like molasses cannot pass through the small pores of the tubing.
• 💧 Small molecules, such as water, can pass through the membrane.
• 🔬 The experiment compares the osmotic pressure inside and outside the tubing.
• 📏 Two samples are prepared: one with molasses inside the tubing and one without.
• 🎚️ The control sample remains unchanged, showing no effect of osmosis.
• ⏱️ The experiment is observed over a period of 2 hours to observe changes.
• 📈 A significant change in volume is observed in the sample with molasses.
• 📉 The viscosity of the molasses inside the tubing decreases, indicating dilution.
• 🔍 The water molecules move through the tubing, driven by osmotic pressure, diluting the molasses.

Q & A

What is dialysis tubing?

Dialysis tubing is a semi-permeable membrane that allows small molecules to pass through while preventing the passage of larger molecules.

How does the size of molecules affect their ability to pass through dialysis tubing?

Small molecules can pass through the tiny holes in the dialysis tubing, while larger molecules cannot due to their size.

What is the purpose of using molasses in the dialysis tubing experiment?

Molasses is used to demonstrate the concept of osmosis, as its large molecules cannot pass through the semi-permeable membrane, and to observe changes in volume and viscosity due to water molecules passing through.

What is the role of the control in the dialysis tubing experiment?

The control in the experiment is a dialysis tubing filled with molasses that is not placed in water. It serves as a comparison to the test sample to observe the effect of osmotic pressure.

How long does the experiment last before observing results?

The experiment is observed after 2 hours to see the effect of osmotic pressure on the molasses inside the dialysis tubing.

What change in volume is expected in the dialysis tubing containing molasses?

An increase in volume is expected as water molecules pass through the semi-permeable membrane into the dialysis tubing, diluting the molasses.

What is the expected change in viscosity of the molasses after the experiment?

The viscosity of the molasses is expected to decrease as it becomes diluted with water that has passed through the dialysis tubing.

What evidence supports the fact that water molecules moved through the dialysis tubing?

The change in volume and the decrease in viscosity of the molasses inside the dialysis tubing after the experiment indicate that water molecules have moved through the membrane.

What is the driving force that causes water molecules to move into the dialysis tubing?

Osmotic pressure is the driving force that causes water molecules to move through the semi-permeable membrane into the dialysis tubing, diluting the molasses.

Why does the control dialysis tubing remain unchanged?

The control dialysis tubing remains unchanged because it is not exposed to water, and thus there is no osmotic pressure acting on it to cause dilution.