Egg Osmosis Lab
Name: __________________________
Introduction:
Cells have an outer covering called the cell membrane. This membrane is selectively permeable; it has
tiny pores or holes that allow objects to move across it. The cell membrane controls what moves in an
out of the cell. Food and oxygen move into cells across the cell membrane through the process of
diffusion. Diffusion is the movement of a substance from an area of high concentration to an area of
low concentration. Osmosis is a special type of diffusion – it is the diffusion of water across a selectively
permeable membrane. Osmosis occurs when water moves from an area where it is more concentrated
to an area where it is less concentrated.
We are going to use eggs to observe the process of osmosis. Please complete the following lab report
carefully. All parts of this lab will be marked individually.
Purpose: To observe how osmosis can affect the mass of an egg after being soaked in various liquids.
Materials:
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3 raw eggs, shells in tack
300 mL of vinegar x 3
300 mL of tap water, salt water, and corn syrup
metric tape
a scale
marker
masking tape
Hypothesis:
Predict how the egg will respond after each of the following conditions:
1. After being soaked in vinegar for 24 hours:
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2. After being soaked in tap water for 24 hours:
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3. After being soaked in salt water for 24 hours:
4. ______________________________________________________________________________
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5. After being soaked in corn syrup for 24 hours:
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Procedure: **wash hands carefully after each step – raw egg can contain salmonella
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
Weigh and record the mass of each egg in the table.
Place each egg in individual beakers with 300 mL of vinegar in each one.
Allow each egg to soak in the beaker for 24 hours.
Record your observations.
Gently dry off each egg.
Weigh and record the mass of each egg.
Clearly label each beaker with masking tape titled tap water, salt water, and corn syrup.
Put 300 mL of each liquid in each labelled beaker or jar.
Place one egg in each beaker or jar. Allow to sit for 24 hours.
Remove eggs from beakers and gently dry off.
Weigh each egg and record mass in table.
Record observations.
Observations:
Mass Data Table
Egg
Circumference
cm
Vinegar
weight in
grams
Tap Water
weight in
grams
Salt Water
weight in
grams
Corn Syrup
weight in
grams
Vinegar
Tap Water
Salt Water
Corn Syrup
1
2
3
Observation Data Table
Egg
1
2
3
Circumference
Use a bar graph to graph the changes in mass after each day. (Refer to the bar graph we created in the
gummy bear osmosis lab to help). Remember to clearly label your graph. You might need to include a
legend.
Analysis Questions: Be sure to use appropriate scientific vocabulary when responding to questions.
1. What liquids caused the egg to swell?
2. What liquids caused the egg to shrink?
3. Explain why some eggs swelled and some eggs shrunk using the concept of osmosis.
Criteria
Knowledge and
Understanding
Thinking
Communication
Application
Level 1
Demonstrates
limited
understanding of
osmosis and
diffusion and how
they work in
organisms.
Uses scientific
inquiry to develop
a vague
hypothesis and
draw few
conclusions about
an experiment
involving osmosis.
Uses limited
scientific
vocabulary when
communicating
the results of an
experiment.
Organizes
information into
bar graphs to
show comparisons
with limited
effectiveness.
Uses bar graph
with limited
effectiveness to
draw conclusions
about an
experiment.
Level 2
Demonstrates
some
understanding of
osmosis and
diffusion and how
they work in
organisms.
Uses scientific
inquiry to develop
a hypothesis and
draw some
conclusions about
an experiment
involving osmosis.
Level 3
Demonstrates
good
understanding of
osmosis and
diffusion and how
they work in
organisms.
Uses scientific
inquiry to develop
a hypothesis and
draw conclusions
about an
experiment
involving osmosis.
Uses some
scientific
vocabulary when
communicating
the results of an
experiment.
Organizes
information into
bar graphs to
show comparisons
with some
effectiveness.
Uses bar graph
with some
effectiveness to
draw conclusions
about an
experiment.
Uses good
scientific
vocabulary when
communicating
the results of an
experiment.
Organizes
information into
bar graphs to
show comparisons
with effectiveness.
Uses bar graph
with good
effectiveness to
draw conclusions
about an
experiment.
Level 4
Demonstrates
thorough
understanding of
osmosis and
diffusion and how
they work in
organisms.
Uses scientific
inquiry to develop
a strong
hypothesis and
draw effective
conclusions about
an experiment
involving osmosis.
Uses thorough
scientific
vocabulary when
communicating
the results of an
experiment.
Organizes
information into
bar graphs to
show comparisons
with limited
effectiveness.
Uses bar graph
with excellent
effectiveness to
draw conclusions
about an
experiment.