Amount of Antioxidants in Three Green Tea Samples

And finally into test tube 3, I pipetted 1.0 ml turnip extract and 4.0 ml of water. The contents of test tube 1 was poured into a spectrometer tube and labeled it “B” for blank. “B” tube was now inserted it into the spectrometer. An adjustment to the control knob was made to zero the absorbance reading on the spectrometer since one cannot continue the experiment if the spectrometer is not zeroed. A combination of two people and a stop watch was now needed to not only record the time of the reaction, but to mix the reagents in a precise and accurate manner. As my partner recorded the time, I quickly poured tube 3 into tube 2. I then poured tube 2 into the experiment spectrometer tube labeled “E” and inserted it into the spectrometer. A partner then recorded the absorbance reading for every 20 seconds for a total of 120 seconds. After the experiment, a brown color in the tube should be observed to indicate the reaction was carried out. Using sterile techniques, any excess liquid left was disposed

Procedure: I used a ruler, thermometer, and scale to take measurements. I used a graduated cylinder, short step pipet, scale, and ruler to determine volume and density. I used a volumetric flask, graduated pipet, pipet bulb, scale, and glass beaker to determine concentrations and densities of various dilutions.

In the lab we filled the first beaker up with water. Then we took a pipet (filled with the liquid) and dropped water droplets onto the

The boiling flask will be put into a beaker which will contain water that will be warmed up through the process. Then, the condenser will be placed in to the beaker perpendicular to the floor which will make the reflux process available.

Place the beaker on the hot plate, place the thermometer in the beaker and set the hot plate to 5oC.

3.6.3. 2, 4 – D (2, 4–Dichloro phenoxy acetic acid) stock solution (1mg/ml): 10.0mg of 2.4-D being weighed and dissolved completely in 1N NaOH to a final total volume

1.) Measure out 20ml out of the water and place it into a glass beaker

Acidic Relations in Chemistry is the topic of this experiment. In this experiment, the scientists will be testing the strength of pH and the amount of TDS (total dissolved liquids) in both gunpowder green tea and caffeinated black coffee. The independent variables are the caffeinated beverages and the dependent variables are the pH and TDS levels of the gunpowder green tea and black coffee. The constants are the way we measure the pH and TDS of the caffeinated beverages

1. Gathered all required materials to designated lab bench. 2. Considered all safety precautions including the prevention of spilling water to avoid falls, handling glassware carefully to prevent shattering, avoiding long periods of working with warm water to avoid burns and avoiding the digestion/inhalation of by-products produced after the reaction (e.g. ethanol and carbon dioxide gas). 3.

Pour approximately 50 mL of room-temperature distilled water into the glass beaker by using the estimated volume on the beaker.

1. Fill up a 200ml beaker with tap water and then pour it into the designated jar

14. Using the well D1 pipet, add two drops of the HCI to the well A1 buffer.Use a toothpick to stir the solution.

The pipette was used to transfer 8 mL of the 0.5 molarity solution into the graduated cylinder. Distilled water was added to raise the bottom of the meniscus to the 20.0 mL line and the solution was transferred into the beaker after it was rinsed with the solution. The pipette was used to take a small quantity of the solution and rinse and then fill a test tube with the solution. The amount of 0.2 molarity solution needed to create 20.0 mL of 0.1 molarity solution was calculated as 10.0 mL. The pipette was used to transfer 10.0 mL of 0.2 molarity solution into the graduated cylinder and distilled water added until the bottom of the meniscus reached the 20.0 mL line. The solution was transferred to the rinsed beaker and then a portion placed into a test tube that had been rinsed with the solution. The amount of 0.1 molarity solution required to create 20.0 mL of 0.05 molarity solution was calculated to be 10.0 mL. The pipette was used to transfer 10.0 mL of 0.2 molarity solution into the graduated cylinder and distilled water added until the bottom of the meniscus reached the 20.0 mL line. The solution was then placed into a beaker that had been rinsed with the solution and then into a rinsed test

Turnips and horse radish roots are rich source of this enzyme. In this experiment, we would carry out a reaction between hydrogen peroxide and guaiacol which is colorless dye, using peroxidase as a catalyst, to produce water and an oxidized form of guaiacol which is brown. The formation of brown color would serve as an indicator that the breakdown of Hydrogen Peroxide took place. The enzyme activity would be directly proportional to the brown color intensity. The color intensity would be measured using a spectrophotometer and standardized to find the corresponding concentration for each absorbance unit.

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.