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Using potatoes for osmosis and diffusion labs.
- Teach or illustrate multiple concepts
- Use simple consumable materials and readily available lab items
- Involve weighing, measuring and calculating
- Require the students to make a HAND-MADE graph
- Provide a perfect visual of the concepts I teach in the classroom
- Reinforce the use of lab equipment and proper laboratory skills
- Require the students to use critical thinking and problem solving skills
- Require students to closely examine the date in order to draw a conclusion
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The Osmosis Lab
Introduction: The Osmosis Lab
The project idea is to apply an experiment that circulates around diffusion which is the diffusion of water molecules through a membrane which is the potato cores in this experiment. The aim of this project is to find the effect of the sucrose concentration on the mass of the potato. It's considered an essential project because it demonstrates new ideas about a lesson in science which is diffusion.
Step 1: Problem or Question
The experiment was about measuring the mass of potato cores before and after placing them inside a tube of distilled water, and 5 tubes that consist of differently concentrated solutions of sucrose in water. The research question that this experiment circulates around is how the increase in the concentration of sucrose in water affects the mass of the potato ?. Accordingly, the goal of this experiment is to discover the effect of differently concentrated solutions on the mass of the potato cores.
Step 2: Hypothesis
If the concentration of sucrose increases, then the mass of the potato cores will increase accordingly and this can be proved in the process of osmosis. In which osmosis occurs to balance between the concentration of water in a substance and in the air which adds water to air and this makes the air denser. Moreover, the potato cores mass will increase due to adding more amounts of sucrose, because when adding more amounts of sucrose the potato will swallow more sucrose which has a certain mass that will be added to the potato.
Step 3: Variables
Variables are the factors in an experiment that can be controlled, changed (affected), or measured in an experiment. The variables are divided into three different types which are the controlled variable, dependent variable, and the independent variable.
Dependent variable:
The mass of the potato cores is the dependent variable because it gets affected due to the change in the concentration of sucrose. The mass of the potato cores can be found using the weight balance which gives the mass of the potato cores in grams.
Independent variable: The concentration of sucrose is the independent variable in the experiment because the higher concentration of sucrose increases the mass of the potato cores. Moreover, the concentration of sucrose changes as the potato cores get exposed to different concentrations of sucrose which are 0.2, 0.4,0.6, 0.8, and 1.0 in order to determine the relationship between the concentration of sucrose and the potato cores mass.
Controlled variable: The water is the controlled variable because it stays constant and can be controlled by adding more amounts of water or fewer amounts of water into the testing tubes.
Step 4: Background Research
The mass is one of the factors that can be recognized from the background research because it's an essential part of many experiments. Mass is defined as a unit that measures the size of an object as weight in grams (for low weight objects), in kilograms for heavy objects, and in ton for superheavy objects such as machines. In addition, is an essential part of this experiment which is considered as a type of diffusion that can be defined as the movement of water molecules from areas of higher concentration to areas of lower concentration through a membrane. Osmosis is very similar to the other types of diffusion, in which there is only one factor that makes it different or special which is the fact that it's applied only for water molecules.
Step 5: Materials
Potato coring device
6 testing tubes
Distilled water
Weight balance
0.2 ml of the solution in water
0.4 ml of the solution in water
0.6 ml of the solution in water
0.8 ml of the solution in water
1.0 ml of the solution in water
Safety equipment: safety goggles and the lab coat
Step 6: Procedure
Before starting the experiment there were tools that were required for safety precautions which are the safety goggles the lab coat, and gloves.
-First, prepare the materials that are required for the experiment.
-Second, pour distilled water in a beaker then pour it into the testing tube until it's filled up and name it as distilled water.
-Third, pour water into the beaker then pour the water with a concentration of 0.2 ml of sucrose into the second testing tube and name it as s1.
-Fourth, pour water into the beaker then pour the water with a concentration of 0.4 ml of sucrose into the third testing tube and name it as s2.
-Fifth, pour water into the beaker then pour the water with a concentration of 0.6 ml of sucrose into the fourth testing tube and name it as s3.
-Sixth, pour water into the beaker then pour the water with a concentration of 0.8 ml of sucrose into the fifth testing tube and name it as s4.
-Seventh, pour water into the beaker then pour the water with a concentration of 1.0 ml of sucrose into the sixth testing tube and name it as s5.
-Eighth, Use the coring device to cut the potato into 12 small pieces, then remove the potato skin using the razor blade.
-Ninth, measure the mass of two potato cores using the weight balance.
-Tenth, place 2 potato cores in each testing tube and check them after 24 hours.
-Eleventh, remove the potato cores from the testing tubes and measure the weight of each two.
-Finally, record the observations and take notes.
Step 7: Data Table
Step 8: Graph
Step 9: Data Analysis
It's clearly noticeable that there is a positive relationship between the solution's concentration and the mass of the potato in which as the solution's concentration increases, the mass of the potato cores increases. In other words, the mass of the potato cores (dependent variable) depends on the solution's concentration (Independent variable) to change (positively because it increases) and throw out the experiment. For instance, when the potato cores were exposed to the first solution (0.2 g/l) the potato cores had a mass of 10.68, while when the potato cores were exposed to another solution of 0.4 g/l it had a mass of 10.72.
Step 10: Results
The results of the experiment were as the following, the potato cores which were exposed to the first solution with a concentration of 0.2 g/l had a mass of 10.68, the potato cores which were exposed to the second solution with a concentration of 0.4 g/l had a mass of 10.72, while the potato cores which were exposed to the third solution with a concentration of 0.6 g/l had a mass of 10.76. Furthermore, the potato cores which were exposed to the fourth solution with a concentration of 0.8 had a mass of 10.80, finally, the potato core that were exposed to the fifth and lastsolution with a concentration of 1.0 had a mass of 10.84.
Step 11: Conclusion
Since the data shows that the potato cores which were exposed to solution 1 which has a concentration of 0.2 g/l had a new mass of 10.68 g, the potato cores which were exposed to solution 2 which has a concentration of 0.4g/l had a new mass of 10.72 g, and the potato cores which were exposed to the solution 3 which has a concentration of 0.6 g/l had a new mass of 10.76g, the potato cores which were exposed to the solution 4 which has a concentration of 0.8 g/l had a new mass of 10.80 and the potato core which were exposed to the solution 5 which has a concentration of 1.0 had a new mass of 10.84. For that reason, the hypothesis is correct, In which each time the concentration increases, the mass of the potato cores increases accordingly as it has been noticed in the data.
Step 12: Application
This type of research is essential for humanity because it plays an essential role in plant's lives which are an essential factor for human's lives as well, as they provide the necessities for breathing (oxygen) and food. In which osmosis occurs in plants to balance between the amount of water in the air and in the plant in which the plants have higher amounts of water than air, so water diffuses into the air until the amount of water in both the plant and air is equal. But if the plant is not watered to replace the lost amount of water, it wouldn't survive so obviously it will die. This topic could be practiced in various experiments such as gummy bears and sugar cubes by exposing them to solutions with different concentrations.
Step 13: Evaluation
I utilized Communication skills by giving an introductory video that includes the necessary means to present my idea in the project clearly which included a background related to the topic. In addition, I added some photos that clearly showcase the part of the project that I am discussing (in the instructable).
Step 14: List of Refrences
Images used:
https://www.google.com/search?q=problem&safe=stric...
https://www.google.com/search?q=hypothesis&safe=st...
https://www.google.com/search?q=variables&safe=str...
https://www.google.com/search?q=background+researc...
https://www.google.com/search?q=materials+in+exper...
https://www.google.com/search?q=procedure&safe=str...
https://www.google.com/search?q=data+analysis&safe...
https://www.google.com/search?q=osmosis+lab+&tbm=i...
https://www.google.com/search?q=real+life+applicat...
https://www.google.com/search?q=evaluation&tbm=isc...
https://www.google.com/search?q=results&safe=stric...
https://www.google.com/search?q=references&safe=st...
The experiments data:
Due to the current situation and Covid-19, I couldn't collect the required materials to perform the experiment for that reason, I relied on data derived from another person's experiment.
Science Experiments On The Osmosis Of A Potato
Osmosis, the process in which solvent molecules move from an area of lower solute concentration to an area of higher solute concentration, can easily be demonstrated with potato experiments. Potatoes are full of both water and starch, and will gain water when immersed in watery solutions. Conversely, they will lose water when in concentrated solutions, such as those containing a great deal of starch. You can use potatoes to set up osmosis experiments for students of all ages and levels.
Potatoes in Saltwater
Cut a potato in two, and immerse one of the halves in a very salty solution of water — one containing a quarter cup of salt in a cup of water. Immerse the other piece in tap water containing no added salt. Leave both in their respective solutions for half an hour, then remove the potato halves from their solutions and observe their differences. The one in the salty solution will have shrunk, indicating that water is diffusing from a less concentrated solution to a more concentrated solution. The one in the tap water solution, in contrast, will actually swell slightly, indicating that it is taking in water.
Salt, Sugar and Pure Water
This experiment helps students to differentiate between different degrees of concentration gradients. Make one salt water solution, one sugar water solution, and for the third solution, simply use tap water. Make three thin potato slices — 1/2 cm thick. Place each potato slice into each of the solutions, and leave the slices in the solutions for a half hour.
Observe that the slice placed in salt is very flexible, while the slice placed in sugar is flexible, but less so. Since potatoes already contain sugar, less water will diffuse out of the potato placed in sugar water. The slice placed in water will be rigid, since it will absorb water.
Potato Lengths in Saline Solutions
Give your students potato "cylinders" that are uniform in length and size: for instance, you could cut them to be 70 mm in length and 7 mm in diameter. Make solutions of saline in three different concentrations, 20 percent, 0.9 percent and 0.1 percent. Have the students measure the lengths and diameters of the potato cylinders before and after soaking them in the saline solutions for half an hour. Then, have them calculate the changes in the lengths and diameters of the cylinders, and plot the saline concentrations versus the changes.
Potato Cube Weights
Cut potatoes into four groups of small, uniform cubes measuring 1/2 cm by 1/2 cm. Make four different solutions of sucrose: 10 percent, 5 percent, 1 percent and 0.01 percent. Weigh each group, on a mass balance, before immersing it in the appropriate sucrose solution for half an hour. After immersion, weigh each group again and have your students calculate the changes in the potato masses. Ask them to comment on why a group gained mass, lost mass or retained the same mass.
- The Teachers Corner: Science Experiment–Osmosis
Cite This Article
Lobo, Tricia. "Science Experiments On The Osmosis Of A Potato" sciencing.com , https://www.sciencing.com/science-experiments-osmosis-potato-8360195/. 26 April 2018.
Lobo, Tricia. (2018, April 26). Science Experiments On The Osmosis Of A Potato. sciencing.com . Retrieved from https://www.sciencing.com/science-experiments-osmosis-potato-8360195/
Lobo, Tricia. Science Experiments On The Osmosis Of A Potato last modified August 30, 2022. https://www.sciencing.com/science-experiments-osmosis-potato-8360195/
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Mar 26, 2020 · In this activity, we are going to explore osmosis by looking at a dataset produced with a classic classroom experiment. The experiment uses pieces of potato that are placed in six different solutions of water each with a different solute concentration. The solute is sucrose and the concentrations are measured in units of molarity.
The following experiment investigates the effect of different concentrations of sucrose close sucrose A disaccharide made from glucose and fructose. It is used as table sugar. on potato tissue. It ...
The potatoes are allowed to sit in their various solutions overnight. After 24 hours they are weighed to determine their final mass. The student will calculate a percent change in mass and place this data on a graph. From the graph, the student will determine the solute concentration of the potato.
Ideally, you prepare 9 cores, so you can do your experiments in triplicates. Push the corer or borer all the way through the potato and remove the core carefully so the potato piece stays intact. Alternatively, you can cut the potato into strips that should all have the same dimensions. They should be at least ½ inch thick and two inches long.
Experiment: Osmosis in Potatoes • Distribute two slices potato to each group. • Give each pair: – 1 Potato Activity Sheet, one 100 mL beaker of distilled water, 1 container of salt, 1 spoon, 1 petr i dish and lid labeled #1- water, 1 petri dish and lid labeled #2- salt, 2 rectangles of potato. Tell students to: 1.
What will keep potatoes (or other veggies) fresher: soaking it in regular water or saltwater? This month, I’m going to explain this question by explaining the concept of osmosis. Osmosis is a property of matter that deals with diffusion; a spreading out of particles from high concentration to low concentration.
This activity will enable you to explore the relationship between the surface area, volume and rate of diffusion by experimenting with model “cells.” In this investigation, cells will be represented by cubes of potato in which the rate of diffusion will be measured. The cubes will be put into a solution of iodine.
In other words, the mass of the potato cores (dependent variable) depends on the solution's concentration (Independent variable) to change (positively because it increases) and throw out the experiment. For instance, when the potato cores were exposed to the first solution (0.2 g/l) the potato cores had a mass of 10.68, while when the potato ...
Apr 26, 2018 · Osmosis, the process in which solvent molecules move from an area of lower solute concentration to an area of higher solute concentration, can easily be demonstrated with potato experiments. Potatoes are full of both water and starch, and will gain water when immersed in watery solutions.
Experiment -2 Aim: To demonstrate the process of osmosis with the help of a potato osmoscope. Requirements: A petri-dish, water, 20% sugar solution, a potato, a knife and some paper pins. Procedure: 1. Cut one side of the potato tuber to obtain a flat surface. 2. Bore a deep cavity in the flat surface with a thin base left. 3.