Throughout this report you will gain information as to how temperature effects the amount of oxygen produced in an enzyme- catalase experiment. In the experiment we used liver extract as a catalase and created a chemical reaction within a reaction chamber between the catalase and hydrogen peroxide as well as three different controlled temperatures. In the procedure below there will be a step by step process as to how the experiment was created. As a result we found that the higher the temperature in the water bath the more oxygen will be produced and “rejected” from the reaction chamber. In conclusion, the reaction chamber placed in the highest temperature water bath produced an average of .5 more milliliters of oxygen than the reaction chamber placed in the lowest temperature water bath tested. While doing scientific research previously in the week, students found information about enzymes and how they work. In the concentration of catalase lab students found that the less enzyme concentration present, the less oxygen is produced. According to Science.com chemical reactions occur when two or more compounds collide. A chemical reaction occurs when any two substances come together to form one.
In the first enzyme experiment dealing with concentration when the catalase disks came in contact with the hydrogen peroxide it created a chemical reaction which in turn caused oxygen to be produced. When the concentration of the catalase disks were reduced (decrease the number of disks in the experiment) less oxygen was produced because the hydrogen peroxide had less catalase to react with, hence the reason for decreased amount of oxygen in milliliters at the end of the five minute experimentation time period. The goal for the original (concentration) experiment was to see how the concentration levels of the catalase effected the amount of oxygen produced. That was just a base line for what was to happen next. As a class we divided and conquered to dig deeper into a more controlled experiments to figure out what really was effecting the amount of oxygen produced. My group focused on temperature. If the temperature of the water bath that the reaction chamber is placed in is increased then the amount of oxygen produced will increase. The independent variable is the temperature of the water and the dependent variable is the amount of oxygen that is produced. (In milliliters)
Here is an example of how I would have written a lab procedure for other people attempting the experiment. Materials:
• 4, 50mL beaker’s, with 1 containing fresh catalase solution
• Reaction chamber
• Filter paper disks
• Ring stand & clamp
• 10mL graduated cylinder
• 100mL graduated cylinder
• 3% hydrogen peroxide (H2O2)
• pan (water bath)
• Hot plate (along with heat protectant gloves)
• distilled water
1. Work as a lab group of 3-4 members. Each lab group will complete Part A of the lab and repeat.
2. At your lab table you will find a square bottle with a medicine dropper top. This is called the Reaction chamber. You will also find a 100mL graduated cylinder, ring stand and clamp, and a Plastic pan which will be used as a water bath. All of this equipment needs to be assembled into our experimental apparatus, as described and illustrated below.
3. Fill the pan 3/4 full of tap water and ice to cool the water to 7 °C
4. Submerge the 100mL graduated cylinder to fill it with water. Turn the graduated cylinder upside down, keeping the open end under water, so as to keep it filled with water. Suspend it upside down in the clamp on the ring stand. Adjust the height of the clamp on the ring stand so the open end of the graduated cylinder is about 3cm above the bottom of the pan. 5. Place a thermometer in the pan and record the temperature of the water, during Part
A of the lab. For this experiment it should be around 7 degrees Celsius.
1. Set up the experimental apparatus as described above.
2. Obtain a small amount of stock catalase solution in a 50mL beaker. (Put on ice to keep catalase cool)
3. Obtain a reaction chamber and a number of filter paper disks. (4 for each trial)
4. Prepare 4 disks for use in the reaction chamber. Prepare each disk, one at a time, by holding each by its edge with a pair of forceps (tweezers) and dipping it into the stock catalase solution for a few seconds. *** Stir your catalase solution (liver extract) before every disk is dipped. Remove the excess liquid from the disk by blotting the disk on a paper towel. With another paper towel dry the tip of the forceps, so it doesn’t drip in the next step.
5. Next, transfer the dampened disks to the top interior wall of the reaction vessel. The wet filter paper disks will stick to the side wall of the glass. Position the disks in the upper half of the reaction vessel (the half near the opening). Repeat this procedure with the other disks, placing all disks on the same surface of the reaction vessel. * One person is each group should soak and handle all disks for all experiments. In this way, the techniques will remain similar and key operations will be performed consistently. Place four catalase-soaked filter paper disks high on one interior sidewall of the reaction chamber.
6. Stand the reaction chamber upright and carefully add 10mL of 3% hydrogen Peroxide (H2O2) solution. Do NOT allow the peroxide to touch the filter paper disks.
7. Tightly put the stopper on the chamber.
8. Retrieve the water bath and graduated cylinder. Turn the graduated cylinder upside down into an upright position, keeping its mouth underwater at all times.
9. Carefully place the reaction chamber and its contents on its side in the water bath. Make certain that the side with the disks faces upward.
10. Move the graduated cylinder into a position so that its mouth comes to lie directly over the tip of the mouth of the reaction chamber so that any O2 released from the reaction chamber will collect in the graduated cylinder. One member of the team should hold it in this position for the duration of the experiment.
11. Rotate the reaction chamber 180° onto its side so that the hydrogen peroxide solution comes into contact with the catalase-soaked disks. Note the time. This is time “zero”.
12. Measure the gas levels in the graduated cylinder at 30- second intervals for 5 minutes. Record the levels in a data table of your own design.
13. Repeat the experiment from Part A, using 2 different temperatures: 27 degrees Celsius and 37 degrees Celsius. You may easily do this by using the following procedures: a. 27 degrees Celsius: follow the procedure from Part A, but use a combination of water and ice to get the correct temperature. b. 37 degrees Celsius: follow the procedure from Part A, but use a hot plate to warm water to the correct temperature.
14. Record all data in a data table of your own design. Save information to make a graph.
15. Plot the data for Parts A and B on the same set of axes.
Throughout the experiment we made various observations all having to do with the effect that the temperature had on the amount of oxygen being produced and coming out of the reaction chamber. For setting up the experiment we realized that maintaining the desired temperature with minimal change in the degree of Celsius was something that had to be maintained and watched closely. When it came to the actual experiment the 7 degree Celsius water bath produced less oxygen in a time period of 5 minutes increasing at a steady rate of .1 milliliters per every 30 seconds. Overall the 27 degree Celsius water bath produced at a rate of .2 milliliters per 30 seconds. Finally, the 37 degree Celsius water bath produced at a rate of .5 milliliters per 30 seconds. Though the difference in oxygen being produced per second is minimal, as the temperature increases it is clear that more oxygen is being produced in the 5 minutes than when the water is cooler given the same amount of time. Below is a set of data that we collected during the experiment along with a line graph showing our findings and equations that go along with our information. Time (seconds)
Looking through results the hypothesis of “If the temperature of the water bath that the reaction chamber is placed in is increased then the amount of oxygen produced will increase” was a correct statement for the most part. As temperature increased the amount of oxygen produced increased as well. In the tooth-pick lab students posed as enzymes and did various things to test what may affect the performance of an enzyme one of those things being temperature. In that lab students were asked to place their hands in an ice bath for a certain period of time (2 minutes I believe), in turn numbing our hands (the enzyme). The results were the same as what was predicted in our temperature experiment, the number of tooth-picks broken was dramatically decreased after having our hands in the ice bath. This has direct correlation to what we had tested in the procedure above. To better our experiment and get more accurate results we could have had more control over the temperature of the water bath, other than that the experiment created and tested had matched our hypothesis and had reasonable results that we could back up with scientific information.
The reaction chamber placed in the highest temperature water bath (37 degrees Celsius) produced an average of .5 more milliliters of oxygen than the reaction chamber placed in the lowest temperature water bath tested (7 degrees Celsius).
Eric Hammer, Amy Carson (August 26, 2012) Understanding Why Chemical Reactions are so Violent.
Retrieved From http://www.brighthubeducation.com/science-homework-help/ K.Hammann, S. Elliott (October 3, 2013) Catalase Concentration Lab. Retrieved From room S240/ K. Hammann, S. Elliott (October 1, 2013) Toothpickase Lab Activity. Retrieved From room S240/