Osmosis Formal Lab Report Example
Research Question: In this investigation, you will determine whether different solutions are HYPOtonic,
ISOtonic, or HYPERtonic relative to the inside of a Gummy Bear.
I.
Purpose:
The purpose of this lab is to determine the effect(s) of certain solutions on a Gummy Bear. The three solutions
that will be used are a sugar water solution, distilled water, and a salt water solution. Based on the results of the
lab, it is to be determined which of these three solutions are hypotonic, hypertonic, or isotonic.
II.
Background Information:
Diffusion “is the movement of molecules in a fluid or gas from a region of higher concentration to a region of
lower concentration” (Nowicki, 2008). Osmosis is a type of diffusion that specifically deals with the movement
of water from a region of higher concentration to lower concentration. There are three types of solutions that
will be explored in this experiment.
1. Isotonic solution: a solution in which the cell and the solution have the same concentration of water
and solutes inside and outside of the cell. This allows water to flow into and out of a cell at equal
rates, meaning the cell will always stay the same size.
2. Hypertonic solutions: a solution in which the cell and the solution do not have the same
concentration of water and solutes inside and outside of the cell. In a hypertonic solution, there are
more solutes outside of the cell than inside of the cell, which will cause the water to go from a region
of higher concentration (inside of the cell) to a region of lower concentration (outside of the cell).
This flow of water out of the cell causes it to shrink.
3. Hypotonic solutions: a solution in which the cell and the solution do not have the same concentration
of water and solutes inside and outside of the cell. In a hypotonic solution, there are more solutes
inside of the cell than outside of the cell, which will cause the water to go from a region of higher
concentration (outside of the cell) to a region of lower concentration (inside of the cell). This flow
of water into the cell causes it to expand.
III.
Hypothesis:
If a gummy bear is submerged in a sugar water solution then its size will stay the same because the amount of
sugar inside and outside of the gummy bear acting as an isotonic solution. If a gummy bear is submerged in
distilled water, then it will grow in size because there will be more solutes inside the gummy bear than outside,
acting as a hypotonic solution. If a gummy bear is submerged in salt water, then it will shrink in size because
there will be more solutes outside than inside the gummy bear acting as a hypertonic solution.
IV.
V.
a. Independent Variable: The three solutions. Sugar water, distilled water, and the salt
water.
b. Dependent Variable: The change in Gummy bear size (length, width, weight) for all three
solutions
Materials:
a. List all materials used in the experiment (include ANYTHING you used)
Procedure:
VI.
Data Collection and Processing:
Sugar Water
Concentration
(25/75 H2O)
Original
Weight
(g)
Weight
after 24
hours(g)
Original
Length
(mm)
Length
after 24
hrs (mm)
Original
Width
Width after
24 hrs (mm)
Percent Change
1.new#-original#
2. answer/original
3. x 100 (weight)
Your Info.
Distilled
Water (100%)
Original
Weight
(g)
Weight
after 24
hours(g)
Original
Length
(mm)
Length
after 24
hrs (mm)
Original
Width
Width after
24 hrs (mm)
Original
Weight
(g)
Weight
after 24
hours(g)
Original
Length
(mm)
Length
after 24
hrs (mm)
Original
Width
Width after
24 hrs (mm)
Percent Change
1.new#-original#
2. answer/original
3. x 100 (weight)
Your Info.
Salt Water
Concentration
(25/75 H2O)
Percent Change
1.new#-original#
2. answer/original
3. x 100 (weight)
Your Info.
a. Calculations: Process your data, and include any calculations necessary (percent change? Mean,
median, mode? Etc.)
b. Graphs: Include graphs that show your processed data. Use these to help you support your
conclusion. Always make sure to clearly label your axis. IT IS VERY POSSIBLE (IN FACT,
PROBABLE) THAT YOU WILL NEED MORE THAN ONE GRAPH.
Growth in mm
Length (mm)
6
4
2
0
Sugar Water
Gummy 1
IV.
Conclusions:
Distilled Water
Solultion Type
Gummy 2
Salt Water
Gummy 3
Gummy 4