Bioinorganic Coordination Chemistry Essay

At five minute intervals over the next fifteen minute period, record the color intensity of the solution of each test tube.

3. Carefully felt the sides of the test tube and observed the resulted chemical reaction for about 30 seconds.

4) One package of active dry yeast was added to bottle labeled ‘5mL’ and solution was swirled.

10 microliters of the sample is then added and the assay absorption is measured at 340nm. If absorbance was above 1.5, samples were diluted.

20) If the solid is still not dissolved, add a tiny amount of hexane and swirl again.

8. I added the 3 ml of soap to the beaker and stirred the solution 40-50 times with a fresh pipette.

pH was recorded every time 1.00 mL of NaOH was added to beaker. When the amount of NaOH added to the beaker was about 5.00 mL away from the expected end point, NaOH was added very slowly. Approximately 0.20 mL of NaOH was added until the pH made a jump. The pH was recorded until it reached ~12. This was repeated two more times. The pKa of each trial are determined using the graphs made on excel.

3. We poured tube 1 with the solution in tube 3 to combine them. We repeated this for all of the tubes. Each of the tubes in step 1 was mixed with a tube in step 3, making there be 6 total test tubes with a solution in it.

Make sure to use the same type of cuvette to keep the width consistent and to prevent any experimental error from arising. Obtain 5 of the same type of cuvettes and pre-rinse them thoroughly. Label them numbers one through five in increasing molarity. Then, fill each of the cuvettes with one of the five solutions you created back in Part A. We will first examine the solution that exhibits the highest concentration or molarity. Make sure to wipe the outside of the cuvette with a Kimwipe before placing into the SpectroVis Plus device. Observe the graph that is generated and make sure to take note where the maximum absorbance takes place.

2. If the mineral is non-metallic, decide if it is light or dark in color.

14) Obtain the unboiled chloroplast suspension, mix, and transfer 3 drops to cuvette 3. Immediately cover and mix cuvette 3. Insert it into the spectrophotometer's sample holder, read the percentage transmittance, and record it in Table 4.4. Replace cuvette 3 into the incubation test tube rack. Take and record additional readings at 5, 10, and 15 minutes. Mix the cuvette's contents just prior to each readings. Remember to use cuvtte 1 occasionally to check and adjust the spectrophotometer to 100% transmittance.

3. The spectrophotometer was set at 420nm. Distilled water was also used as the ‘blank’.

In 1937, Robert Hill isolated chloroplasts and demonstrated that chloroplasts can give off oxygen in the absence of CO2. The presence of an electron acceptor, 2,6-dichlorophenolindophenol, otherwise known as DCPIP, will turn from a blue color to clear when electrons have been accepted. This artificial electron acceptor intercepts electrons before those electrons reach PS I. Based upon this chemical feat, this will allow for the measurement the absorbance of 600nm wavelength of cuvettes containing free chloroplast reactions at various conditions, such as the effects of uncouplers (Ammonia), herbicides {3-(3,4-dichlorophenyl)-1,1-dimethylurea} (DCMU), light color, and distance from light. Using the isolated chloroplast, sodium chloride buffer, and the artificial electron acceptor, these manipulations will be carried out and the rate of the reaction measured using a spectrophotometer. The results expressed both the uncoupler and herbicide decrease reaction rate, 30 cm away from a 60 watt light bulb is prime for fast reaction rate, and green light demonstrated the fastest reaction rate.

In the preliminary test I used 3cm3 of DCPIP solution. A large amount of juice was needed to change the colour of the DCPIP to colourless. I changed the amount of DCPIP solution from 3cm3 to 1cm3. This is because less juice will be needed to change 1cm3 of DCPIP from blue to colourless. I used test tubes to hold the DCPIP and the 1% ascorbic acid but it was difficult to mix the two solutions together so I decided to use a boiling tube instead. I tested the 1% ascorbic acid in the preliminary test and I found that I need less than 3cm3 of the solution.

There are thousands of chemical reactions that occur in an organism that make life possible. Most of these chemical reactions occur too slowly on their own. Enzymes are protein catalysts that speed up chemical reactions in a cell. Catalysts are not changed by the reactions they control, and are not used up during the reaction. Enzymes therefore, can be used over and over again. Enzymes are large complex proteins made by the cell and allow chemical reactions to take place at the temperature of the cell. These catalysts are needed in only very small amounts because a single enzyme molecule can complete the same reaction thousands of times in one minute.