In this experiment the student will need a Bunsen burner, ring stand, wire gauze, pH meter, red cabbage, about seven small beakers (clean), seven test tubes, universal pH paper, both red and blue litmus paper, methyl red and several solutions provided by the instructor. First the student will prepare the red cabbage by filling a beaker with 50 mL of distilled water and placing about 1 gram of finely chopped red cabbage and boil for 10 minuets. Let the beaker cool and decant the solution from the cabbage. While the cabbage is boiling the student should continue with the rest of the experiment, pour about 2 mL into the beaker and test the pH with the pH meter, litmus papers, and universal pH paper and record. Pour half of the solution into a test tube and set aside. With the sample in the beaker add 2 drops of methyl red and record. With the solution in the test tube add a dropper full of the cabbage indicator and record. The student must do these steps with all of the solution provided for in this experiment.…
Experimental Procedure: This lab follows the experimental procedure of the book as outline in the Mayo book on pages 133 and 134. However; the following modification were made to the procedure:…
We will be using the LoggerPro and LabPro in order to help us determine our data. The purpose of this experiment is to follow the changes of pH during the titration of an acid and a base in order to determine the of the weak acid, . is a constant for a given acid at a given temperature. In this experiment we determined the Ka using two different methods: 1) the measurement of the pH of a solution containing a known concentration of a weak acid, and 2) measurement of the pH at the half-neutralization point in the titration of a weak acid and a strong base.…
The purpose of this experiment was to observe the color change and the concentration to determine the…
In this practical the activation energy of hydrolysis of p-nitrophenyl phosphate will be determined in the presence of the enzyme alkaline phosphatase.…
The optimum pH for the enzyme acid phosphatase was predicted to be within acidic regions and the results obtained showed that the optimum pH was about 5.5 see fig.10. It had the highest absorbance value, meaning it had the most PNP in the tube in the given time and thus the fastest rate of reaction. A change in pH changes the shape of the active site of the enzyme. The bonds within the active site of the enzymes are polar, this means that they are extremely sensitive to ions. The decrease in pH increases the concentration of H+ ions in the solutions, these interact with the polar bonds in the enzymes structure to form individual bonds. This disrupts the shape of the active site and thus the substrate PNPP is no longer complementary to the enzyme’s active site. So no Enzyme substrate complexes can be formed and the rate of reaction drops. The same thing happens when there are extra OH- ions in the mixture. The pH in our cells must be extremely specific and buffered in order to prevent changes in pH and the denaturing of these enzymes. The data collected during these experiments are very similar to those published and studied, meaning the results collected are valid, and thus the experiment…
The purpose of this experiment was to get an understanding as to how to properly prepare chemical buffers. Also part of this experiment was to gauge the effectiveness of the buffers by measuring their pH levels in various titration solutions, using a pH meter.…
Lab 1: Effect of pH on a Food Preservative (we’ll used this as an example)…
Materials and Methods: A buret with NaOH solution was used to ensure an accurate measure of NaOH could be taken. A PH recording machine was used to measure the PH. To make sure 25.0 ml of the unknown was measured, we used a 25.0 ml pipet.…
Title: The Effect of the Number of Drops of HCl and NaOH on the Net Change in the pH of Plant, Animal, and Nonbiological Solutions…
Analysis: In this lab, one observed that acids and bases affect the pH of milk differently from one another. For example, the lemon juice gave the milk a lower pH because of the acidity of the lemon juice. That’s why the milk curdled. Another example, when ammonia was added to milk in part II of the lab, the pH level increased greatly. pH is the symbol for the logarithm of the reciprocal of hydrogen ion concentration in…
To determine the pH of the rat’s whole blood sample, a pH determination will be performed.…
In the experiment, we tested a sodium chloride solution. Along with the tested solution, control groups (water and sodium phosphate) were used to be help understand whether or not NaCl was a buffer. Water was the negative control group and sodium phosphate was the positive control group. If NaCl was a buffer than the pH would be stabled as the sodium phosphate buffer. If NaCl was not a buffer than the pH would fluctuate like the negative control, water. During the first trial and prior to the drops of 0.5 M of HCl acid, the pH of sodium chloride was 7.50. After the addition of 5 drops of 0.5 M of HCl, the pH decreased by 4.83 and ended at 2.67 on the pH scale. When comparing the results of the sodium chloride to the control groups, the total pH change of sodium phosphate was only…
3. Formation of water. (If the reaction is between an acid and a base it is called a neutralization reaction.)…
To determine the effects of pH on catalase enzyme activity and as you increase the pH the more oxygen that will be produced.…