Abstract In this experiment, the reaction kinetics of the hydrolysis of t-butyl chloride, (CH3)3CCl, was studied. The experiment was to determine the rate constant of the reaction, as well as the effects of solvent composition on the rate of reaction. A 50/50 V/V isopropanol/water solvent mixture was prepared and 1cm3 of (CH3)3CCl was added. At specific instances, aliquots of the reaction mixture were withdrawn and quenched with acetone. In addition, phenolphthalein was added as an indicator.
Due to water’s polar structure, ions in some compounds attract and form bonds with water molecules, forming hydrates. A hydrate is a salt that has water molecules trapped within its crystals. Every hydrate has a certain number of water molecules weakly bonded to the salt as follows: salt • number of water molecules Anhydrous salts are salts that can form hydrates but which have had all the water driven off, usually by heat. By heating the Copper (II) sulphate hydrate until its color changes from blue to white, the compound can be decomposed into CuSO4, a white crystal, and H2O gas, represented as follows: CuSO4 • xH2O(s) ←⎯→ CuSO4(s) + xH2O(g) Because of the mass conservation law and the fixed proportion of water molecules, the mole of H2O can be calculated by calculating the mass difference of the substance before and after the reaction: Mole of H2O = (Mass of substance before the reaction) (Mass
In this experiment, the dark blue colour is visible because of the helical amylose and amylopectin reacting with iodine (Travers et al., 2002). The starch-iodide complex forms because of the transfer of charge between the starch and iodide ion and results in spacing between the energy levels. This allows the complex to absorb light at different wavelengths resulting in a dark blue colour (Travers et al., 2002). A blue colour would indicate a positive test while a yellow colour would show a negative test. The Benedict’s test is useful for reducing sugars.
The salt bridge that was used was KNO3 which is potassium nitrate. Potential difference is the work done per unit charge and it is measured in Volts. To measure this it is required that you connect the two half cells to a voltmeter and record the voltmeter reading. The cells must be left in the aqueous solution until there is a voltmeter reading. INVESTIGATIVE QUESTION Is the effectiveness of a half cell determined by the cell potential of that half cell?
TLC, NMR, and IR spectroscopy were used throughout the process to identify ferrocene and acetylferrocene in addition to evaluating the levels of purity. Evidence: The objective of our experiments was to prepare acetylferrocene from ferrocene. The overall reaction was carried out using 6.1 equivalents of liquid acetic anhydride to 1.8 equivalents of phosphoric acid and concluded with an aqueous workup with NaOH. The initial reaction mixture containing ferrocene, acetic anhydride, and phosphate acid was mixed on a hot stir plate. During this period, reflux was observed, and the mixture appeared dark brown in color.
Introduction: In this lab, of water in a hydrate, or a substance whose crystalline structure is bound to water molecules by weak bonds, is determined by heating up a small sample of it. By heating, the water of hydration, or bound water, is removed, leaving only what is called an anhydrous compound. Based on the percent water in the hydrate, it can be classified as one of three types: BaCl2O ⋅ 2H20, with a percent water of about 14.57%, CuSO4 ⋅ 5H2O, which has about 36.0%, and CuCl2 ⋅5H20 (21.17%). Materials: Ring stand, ring clamp, evaporating dish, Bunsen burner, clay triangle, crucible tongs, electronic balance, sample of hydrated salt. Methods: Weight a clean, dry, porcelain evaporating dish on the electric balance and record this mass on an appropriate data table.
The time it takes for the reaction mix to turn blue will be measured with a stopwatch. For the procedure, you will vary the amount of hydrogen peroxide to see how this affects the time the mixed chemicals stay clear before turning blue. The reactions that form the basis for the iodine clock reaction are shown below. Equation 1: H2O2 + 3 I- + 2 H+ → I3- + 2 H2O • H2O2 = Hydrogen peroxide • I- = Iodide ion (from potassium iodide) • H+ = A proton, from hydrochloric acid (HCL) • I3- = Triiodide • H2O = Water Equation
During the experiment, a colourless solution of potassium iodide and a solution of sodium persulfate, starch and thiosulfate will be combined into a beaker to later react into a blue-black complex. The elapsed time from when colourless solutions are combined to the colour change is dependent on the reactant concentrations of sodium persulfate and potassium iodide. Experiments will be conducted by systematically varying the concentrations of persulfate and iodine. The times recorded will be utilised to determine the rate of reaction and
Spectrophotometry Prepared for: Dr. Joseph Dasso By: Lucy Onsarigo Biology 1406 C5L September 23rd, 2014 Introduction Spectophotometry is the ability of molecules to absorb and transmit light energy for determining the concentration of substances in a solution. (Mark Garcia 2014). The instrument used is called spectrophotometer to distinguish different compounds since they absorb light at different wavelength. Some have wide range of wavelength and the shorter the wavelength the higher the energy. For one to know the absorbed light one has to put a cuvette into a sample holder with a solution and record the amount of light transmitted and absorbed through the solution.
The topic that the scientist has researched is the reaction rate of different particle sizes. In the experiment, the scientist will discover how the particle size of Alka Seltzer affects the rate of chemical reaction with water. The independent variable in the experiment is the particle size of the Alka Seltzer, while the dependent variable is the rate of reaction, or the volume of Carbon dioxide. The volume of carbon dioxide will be measured in ml. Also, a few of the constants in the experiment will be the amount of water, and amount of tablets.
To do the temperature and dissolved oxygen tests, stick the probe in the water, and it will show numbers. One will be the dissolved oxygen in ppm (parts per million) and the other will be the temperature of the water. To do the pH test, stick the pH paper in the water and compare the color it turns to the scale. To test nitrates, put clear water in a container and dirty water in another, and put powder in them. Shake them and then compare the color they turn to the scale.
All things considered, the results proved that the unknown substance or element was barium since the calculated density was 3.9 g/mL. To expand upon, the density was calculated by measuring the mass of the metal and using the displacement method to determine the volume of the metal. Also, the best method of disposing the storm water would be to contact a Wastewater Treatment Plant (WWTP) so that they could put it through a purification process, making all that water reusable. Meanwhile, the percent of recovery was calculated by the formula Percent Recovery=observed valuetrue value *100%. Furthermore, according to the pie chart created in the data analysis, the sample given contained of the percent by mass for metal to be 5.2%, salt was 3.3%, wood was 3.1%, plastic was 4.5%, rock was 12.5%, sand was 11.8%, and water was 59.6%.