After each group member performed 20 trials for each type of glassware, we were able to use percent error and standard deviation to determine which types of glassware are accurate and precise. In this experiment, it was important to measure the temperature of the water in order to record accurate densities, which can impact the mass of the water. After finishing the trials, our group subtracted the mass of the glassware without water from the mass of the glassware with water in order to find the mass of the water in grams. Then, we divided the mass of the water by the density(g/cm^3) of the water in order to find the volume (mL). An example calculation from the 5.00mL pipet is: (4.9285mL+4.8839mL+4.9367mL+4.9265mL+4.9134mL)/5 = 4.9178.
After this is done, you then place both test tubes in the water bath for thirty minutes. When you place the test tubes in there label the two wells of the spot place one and two with the wax pencil provided. Finally, add one drop of the iodine solution to each well. Once this is all done, you can then record and analyze your
To determine the effects of two environmental factors, temperature and pH, on the enzyme peroxidase, a spectrophotometer was used to measure the absorbance of each reaction every twenty seconds for two minutes. The temperatures tested were 0°C, 23°C, 32°C, and 48°C; the pH levels tested were pH 3, pH 5, pH 7, and pH 9. The temperatures were kept constant by keeping the tubes at room temperature, or placing them in an ice bath, warmer, or a hot water bath. Peroxidase, hydrogen peroxide, guaiacol and a pH buffer were mixed together to produce a reaction for both the temperature and pH experiments. The optimum temperature for peroxidase activity, 23°C, was determined by taking the highest rate of absorbance of the four temperature reactions
Then transferred each beet to a separate test tube containing deionized water. After 20 minutes in these diffusion solutions, we took the beets out with a dissecting needle and discard it. We then stirred each solution in the test tube with a stirring rod, and transferred it to a cuvette. A spectrophotometer was then calibrated, and used to measure the absorbance of each exposure solution, and diffusion solution. Membrane Damage For the lab experiment for Membrane Damage, we tested the extract pigment and diluted it.
The mixture was then allowed to stir to suspend. Both LB Broth and LB agar mixture were allowed for autoclave for 15 minutes at 121 °C to sterilize. Both solutions were allowed to cool slightly before making additions, such as antibiotics (ampicillin). LB agar was prepared by pouring LB agar solution into petri dishes and allowed to solidify. The petri dishes were seal with parafilm tape and inverted before store at 4 °C together with LB Broth.
The materials that I used in this experiment were six different bands of paper towels; Scott, Giant Eagles “Clean and Tuff”, So- Dri, Brawny, Viva, and Bounty. I also used twelve 88.7 milliliter dixie cups, 50 milliliters of red colored water and a freezer holding the temperature of a negative twenty degrees Celsius. In addition I used a plastic bowl with the dimension of 18 by18 millimeters. And finally I had a piece of elastic string. The procedure for my experiment was not too difficult it just took quite a bit of time.
While OF is considered oxygen-free, its conductivity rating is no better than the more common ETP grade below. It has a 0.001% oxygen content, 99.95% purity and minimum 100% IACS conductivity. For the purposes of purity percentage, silver (Ag) content is counted as copper (Cu). • C11000 - also known as Electrolytic-Tough-Pitch (ETP). Symbol type of copper is the most common.
The substance reacted to blue litmus paper, and red litmus paper underwent no change. Phenolphthalein did not change, and the pH value was 6, a weak acid. The appearance of this substance was a thick, white liquid that had a horrible odor. These observations led me to my conclusion that substance B is spoiled milk. Test-tube C: Test-tube C had ammonia in it.
One must leave the potato cylinders in the two different solutions for at least fifteen minutes because this is a minimum time, in which the starch particles will be able to diffuse into the surrounding liquid, if indeed that is the outcome. Then remove the potato cylinders and dry them out for a second time to rid any excess water which is just clinging to the outside of the potato cylinder, so that the only mass counted, is that of the liquid which is inside the potato. Record their masses and lengths again. For safety reasons I will be very careful when using the scalpel and potato corer. Equipment for my preliminary experiment · One boiling tube with 30cm cubed of distilled water · One boiling tube with 30cm cubed of 1.0M of sucrose solution · Two potato cylinders, approximately the same mass and length
We left the molds in for about twenty minutes and then pulled them out and ran cold water over them in the sink for about a minute. 5. We removed the mold nuts and took out the molded materials. pre-expanded bead procedure 1. First we put the raw beads in the boiling water and let them expand.