Osmosis Eggsperiment

This website sponsored by Adam Equipment has a few very well developed lesson plans/activities for middle and high school students. This particular lesson examines the movement of molecules during osmosis. There are several egg osmosis experiments available on-line. This particular document provides explicit teacher materials, models projected student answers to lab questions and provides very detailed instructions. Included in this lesson plan is a student worksheet available (PDF) that can be downloaded and printed. This experiment is quantitative and provides a wonderful opportunity that assess student performance via a formal lab report.

Weblink address (URL):

Standards & Objectives

Learning objectives:

Purposes:

To demonstrate the osmosis process.
To demonstrate changes in properties of matter.
To expose students to common measuring instruments used in the lab.

Lesson Variations

Blooms taxonomy level:

Applying

Extension suggestions:

What would happen if the concentration of salt is changed? Will the mass of the egg increase or decrease? Why does this happen?
Redo the experiment by leaving the egg in the various solutions for 48 hours instead of 24 hours. Record mass and appearance changes on the observation chart. Discuss how doubling the time that the egg is in the different solutions caused changes in the egg and its mass.
While measuring mass changes every day, also record the egg’s position in the beaker during each of the four daily observation sessions. Explain how the daily changes in the egg’s size changed its buoyancy.
Along with recording the mass of the egg on a daily basis, also measure the remaining volume of solution after the egg has been removed from the beaker. Create a chart to show daily egg mass changes and daily beaker solution changes. Discuss your observations and explain why these changes occurred.

Helpful Hints

Materials:

400 mL beaker
Graduated cylinder
One raw (extra-large or jumbo) egg, shell intact
200 mL white vinegar
200 mL (light) corn syrup
400 mL room temperature tap water, divided
20g salt
Small shallow dish (petri dish, culture dish, foil cupcake cup)
Weighing paper (or filter paper)
Triple Beam (TBB 2610T, 2610g x 0.1g with tare) or Balance
(CQT 251, 250g x 0.1g)

References

Contributors:

Jenise Gordon

Originator:

Ayers Institute for Learning & Innovation