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Researched
by Vanessa R.
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The purpose of this experiment was to determine how the amount of bleach in water affects the growth of radishes.
I became interested in this idea in the third grade when we did a similar experiment in our classroom and I never was able to see the results.
The information gained from this experiment will be used to help prevent the pollutants from getting in our soil and our water.
My hypothesis was the bleach would slow down or damage the radishes in their process of growing.
I base my hypothesis on the fact that bleach is use to oxidize soil and radishes need soil for nutrients and also that bleach is a pollutant.
The constants in this study were:
-The amount of
soil in each cup
-The number of
seeds in each cup
-The amount of
light in each cup
The manipulated variable was the amount of bleach in water that was provided.
The responding variable was the amount the radishes grew.
To measure the responding variable I measured in centimeters from the tip of root to the top of tallest stem.
| QUANTITY | ITEM DESCRIPTION |
| 30 | Radish Seeds |
| 15 | Styrofoam Cups |
| 700 | ml of bleach |
| 1 | 100 watt light bulb |
| 15 | cups of sterile soil |
| 1.1 | liters of water |
| 1 | ruler with metric measurement |
| 3-5 | newspaper pages |
| 3 | plastic containers |
| 1 | pencil |
| 1 | pair of rubber gloves |
1. Gather all materials-
-30 radish seeds
-15 Styrofoam
cups
-700 ml of bleach
-100 watt lamp
-15cups of sterile
soil
-1.1 liters of
water
-1 ruler with
metric measurement
-3-5 newspaper
pages
-3 plastic containers
-1 pencil
-1 pair of rubber
gloves
2. Place newspaper under all the materials
3. Put on rubber gloves
4. Poke 3 holes in each Styrofoam cup with pencil
5. Pour 1 cup of sterile soil in each Styrofoam
cup
6. Place 2 radish seeds 13 cm deep in each cup
7. In a container combine 300 ml of water and
300 ml of bleach and label 1
8. In another container combine 200 ml of water
and 400ml of bleach and label 2
9. In another container pour 600 ml of water
and label 3
10. Label 5 cups group A, another 5 cups group
B, and another 5 cups group C
11. In group A, pour 10 ml of solution 1 in each
cup
12. In group B, pour 10 ml of solution 2 in each
cup
13. In group C, pour 10 ml of solution 3 in each
cup
14. Repeat steps 11-13 every other day
15. Place all cups under 100 watt lamp
16. Turn on lamp
17. Record amount plant has grown each day for
2 weeks
18. At end of two weeks measure from top of stem
to tip of root in centimeters
19. Record all results at end of 2 weeks
The original purpose of this experiment was to see if bleach damaged radishes when mixed with water.
The results of the experiment were that the bleach killed the radishes so that they didn’t sprout. The radishes in the control group grew to an average of 13.7 cm. in length.
See the table and graph below.
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My hypothesis was that the bleach would slow down or damage the radishes in their process of growing.
The results indicate that this hypothesis should be accepted due to the fact that the bleach caused the radishes to not germinate.
Because of the results of this experiment, I wonder if the radishes would grow if affected by a lesser concentration of bleach. I also wonder about other cleanser effect on plants.
If I were to conduct this project again I would provide a longer time of growth and more groups with much lower concentrations of bleach, such as 1/100 bleach and 99/100 of water, 1/10 of bleach and 9/10 of water, 1/3 of bleach and 2/3 of water, etc.
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INTRODUCTION There are different ways bleach is used in the world today. Bleach can be used as a whitening agent for clothes, ivory, teeth, materials, paper, cotton, hair, fur, feathers, string, etc. There are a few different bleaches used. There are for instances hydrogen peroxide and there are other kinds of bleaches such as oxygen bleaches. Hydrogen peroxide is also used as a source of oxygen in fuels for rockets and torpedoes! Bleach is important for people in many different ways. Radishes are a good source of food for humans. It is used in salads and other meals. There are many different kinds of radishes from the Armoracia rusticana (horseradish) to the Raphanus sativus L. (culitivated radish). BLEACH Chlorine dioxide chemical formula is ClO2.ClO2 is used as bleach in pulp and paper. Bleaching is a mixture containing (Ca[OCl]2). Bleaching is a chemical process for whitening any kind of materials. This is done by oxidation reaction that changes coloring matter into colorless substances. Some of the advantages of liquid bleach are that it oxidizes soil, acts as a disinfectant on bacteria and viruses, and it whitens fabrics. Some disadvantages are that extended use on certain fabrics can discolor or fade. Over use on fabrics can leave damage. Some of the advantages of oxygen bleach are that it oxidizes soil, acts as a disinfectant, brightens fabrics, does not fade or discolor fabrics, and it is safe on all fabrics. There are no disadvantages to using oxygen bleach. Until about 1925, the powder was used as a standard agent. In the medieval times in Egypt, China, Asia, and Europe, they practice the method of bleaching by exposure to the sun. Bleaching powder, with the same affect as chlorine, was introduced in 1799 by the Scottish chemist Charles Tennant. HYDROGEN PEROXIDE Hydrogen Peroxide is a chemical compound with Hydrogen and Oxygen with a chemical formula H2O2, two molecules of hydrogen and two molecules of oxygen. Hydrogen Peroxide becomes a solid at 0.41Oc (31.4oF) and may explode violently 100oc (302.4oF). Hydrogen peroxide is used as an oxidizing agent. Oxidation is used for bleaching hair, ivory, feathers, and delicate fabrics. It is also a source of oxygen in fuel mixtures for many rockets and torpedoes. BASES A base is any chemical compound that tastes bitter, feels soapy, neutralizes acids, turns dye litmus blue and turns phenolphthalein pink when the compound is in water solution. Hydroxides of alkimetals are strong bases because they break up completely into hydroxide ions and metal ions when in a water solution. RADISH Another name for the radish is Raphanus sativus
L. and scientific symbol RASA2. Radish is a common name of the mustard
family. Radishes originated in China. They are grown in North
Temperate Zone for they have a strong, smelling root. Radishes or
most commonly used in
SUMMARY Radishes are important, they are a source of food
for people. Other plants are important too. Bleach is a good
cleaning agent. It has a history of the chemist Charles Tennant.
The method of bleaching has been used for a long time. There are
two most commonly used bleaches Hydrogen Peroxide and household cleaning
bleach. Bleach can be used for many purposes some are whitening or
bleaching hair, ivory, feathers, and other delicate fabrics.
"Bleaching," Encarta Encyclopedia 2000, 2000. Gordan, Morris "Base," Encyclopedia Americana, 1999. "Hydrogen Peroxide," Encarta Encyclopedia 2000, 2000. Needles, Howard "Bleach," World Book Encyclopedia, 1991. "Oxygen Bleach vs. Liquid Household Bleach," [Online] Available http://www.prowearappareal.com//oxygenbleach.html, 1999. "Plant Search (Radish)," [Online] Available http://plant_search.cgi, 1999. "Radish," Encarta Encyclopedia 2000, 2000. Squeo, Melissa "What is Bleach and how does it Work?" [Online] Available http://crystal.bioliesufresno.edu:8080/projects/74.html, 1999. Statler, Neil J. "Bleaching," Encyclopedia Americana, 1999. "What is Bleach?" [Online] Available http://clorox.com/science/rmp/how.html, 1999. |
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