Diphenylamine And Electrolyte Lab Report

The preparation for the experiment started by gathering the solutions of enzyme Peroxidase, substrate hydrogen peroxide, the indicator guaiacol and distilled water. Two small spectrometer tubes and three large test tubes with numbered labels. In addition, one test tube rack, one pipet pump and a box of kimwipes were also gathered. Before the experiment, the spectrometer must be set up to use by flipping the power switch to on. Following, the machine was warmed up for 10 minutes and the filter lever was moved to the left. In addition, I set the wavelength to 500 nm with the wavelength control knob. Before the experiment, I had to create the blank solution by pipetting 0.1 ml of guaiacol, 1.0 ml of turnip extract and 8.9 ml water into tube #1. Following the creation of the blank, a control 2% solution was created.

In the experiment we used Turnip, Hydrogen Peroxide, Distilled Water, and Guaiacol as my substances. On the first activity, Effect of Enzyme concentration of Reaction Rate for low enzyme concentration, we tested three concentrations of the turnip extract, and hydrogen peroxide. For the Turnip Extract I used 0.5 ml, 1.0 ml, and 2.0 ml. For hydrogen peroxide we used 0.1 ml, 0.2 ml, and 0.4 ml. We used a control to see the standard, and used a control for each enzyme concentration used. The control contains turnip extract and the color reagent, Guaiacol. We prepared my substrate tubes separately from the enzyme tubes. My substrate tube

The purpose of the experiment is to cycle solid copper through a series of five reactions. At different stages of the cycle, copper was present in different forms. First reaction involves reaction between the copper and nitric acid, and copper changed from elemental state to an aqueous. The second reaction converted the aqueous Cu2+ into the solid copper (2) hydroxide. In the third reaction Cu(OH)2 decomposed into copper 2 oxide and water when heated. When solid CuO reacted with sulfuric acid, the copper returned to solution as an ion (Cu2+). The cycle of reactions was completed with the reaction where elemental copper was regenerated by Zn and Cu

One of the most important skills to have in the chemistry lab is the understanding of how chemicals will react. Knowing for example, how a chemical will react with a metal, is an excellent way of determining the amount of a particular metal in a deposit. This knowledge was used in this lab to determine the amount of copper in an unknown sample mixture. It is also known that the determination of the percent concentration of a certain solution, will directly effect the percent transmission and absorption of a solution, dependent upon its dilution. By first testing known concentrations of a solution, and plotting this information graphically, a line is formed

1. We measured 2 mL of diluted hydrogen peroxide (the substrate), 1 mL of guaiacol (the product indicator), and 1 mL of neutral buffer (pH 7) with a syringe and disposed it into tubes 1, 2 , 4, 9, 11, and 12.

B2.Place a few crystals of copper(II)sulfate pentahydrate in a test tube. Clamp the tube and heat in a horizontal position. One of the products is copper(II)sulfate. What is the other one? This decomposition reaction is easily reversible. Add a dropperful of water to the tube when it cools. Record what happens.

The lab leaders and the Punk Rock Warlord prepared three different concentrations of catechol oxidase by extracting potato juice (because it contains lots of catechol oxidase). Pure catechol, a 5mL test tube, 1mL/5mL

In the blank cuvettes, the 2 mL of pH levels 2,5,7, and 10 were added first, followed by the 1mL of peroxidase. However our experimental cuvettes contained both hydrogen peroxide and guaiacol. Before the cuvettes were placed in the spectrophotometer we added 0.1 mL of H202, followed by 0.02 mL of guaiacol these two substances were added last immediately before they were placed in the spectrophotometer. Para film was placed over the cuvette opening, and the assay solution was shaken and placed into the spectrophotometer where its saturation level was then tested. We recorded the saturation level of the solution every 15 seconds for 3 minutes. This process was repeated two times for each pH level for a total of two trials.

The Copper Cycle is a popular experiment used to determine if an element, in this instance, copper, reverts to its elemental form after a chain of reactions. This experiment is very dangerous because of the reactions between the strong acids and bases. In this experiment I performed a series of reactions starting with copper metal and nitric acid to form copper (II) nitrate. Then I reacted copper and several other solutions such as, sodium hydroxide, sulfuric acid, ammonium hydroxide, and hydrochloric acid to form precipitates. In conclusion my percent recovery

Refer to the reaction of iron nails with a copper solution assignment in Module 3, Section assignment 3.4 Part F of the Chemistry 11 course.

Experimental approach: In the first reaction, copper metal turnings oxidize when put in contact with nitric acid and become copper nitrate.

In this experiment, NaOH was the inhibitor used to stop the enzymatic reactions. NaOH is very basic and when added to a solution, will cause a drastic increase in pH, causing denaturation of the enzyme. The amount of product formed could be calculated by placing the test tube in a spectrometer after the addition on NaOH. A spectrometer measures the absorbance of a solution, which helps compare how much of a substance is in a solution.

When the zinc was added to the copper (II) sulfate solution, the solution started to bubble. As the solution was stirred, it turned a cloudy blue. Small flecks of a brown solid were visible. As the solution became colorless, the brown solid settled to the bottom of the beaker. The solid formed was copper in its elemental state. The color faded from the solution as the copper ions slowly formed into solid copper. The copper was poured into a funnel with filter paper and washed three times with 25 mL

0.5% of copper sulphate solution was added by drop at a time and and the test tube was shaked continuously.

And copper (II) ions were reduced to copper because it gained electrons and its oxidation number changed from +2 in copper (II) ions to 0 in copper.