Osmosis Experiment: Observing Water Movement in Eggs
Objective:
Observe the effect of osmosis on eggs submerged in solutions with varying concentrations
of water and sugar.
Materials:
3 "naked eggs" (prepared in vinegar for 2-3 days), 3 containers with lids, Water (not
distilled), Granulated sugar, Measuring spoons, Flexible measuring tape.
Procedure:
1. Prepare the eggs by soaking them in vinegar for 2-3 days.
2. Measure and record the circumference of each egg.
3. Prepare three solutions:
oSolution 1: Plain water
oSolution 2: Water + 1 tbsp sugar
oSolution 3: Water + 3 tbsp sugar
4. Submerge one egg in each solution.
5. Let the eggs sit for 24-48 hours. Afterward, measure the circumference of each egg
again.
Expected Results:
Solution Initial size
(cm)
Expected Change Final size (cm)
Plain water 16 +1 cm to +1.5 cm 17 - 17.5
1 tbsp sugar solution 16.5 0 cm to -0.5 cm 16 - 16.5
3 tbsp sugar solution 17 -1 cm to -2 cm 15 - 16
Conclusion:
Osmosis occurs as water moves through a semipermeable membrane, causing the egg to
either swell (in plain water) or shrink (in sugar solutions).
Discussion Questions:
1. How did the size of the eggs change in each solution? Explain why the eggs
changed in the way you observed.
2. The egg in plain water swelled up, while the eggs in the sugar solutions shrank.
Why do you think this happened? Use the idea of concentration to explain your
answer.
3. What can you learn from this experiment about how water moves in living cells?
Can you think of real-life examples where osmosis happens in plants or animals?
4. Imagine you are a scientist and you want to test how different liquids (like
saltwater or juice) affect the eggs. What new experiment would you design?
Explain what you would change and why.
5. (Task) What do you think could make this experiment more accurate? List at least
two things you could change in the setup to get more reliable results.