The chemical properties of chemically preserved orange juice are presented in Table 1. The pH of the examined orange juices ranged from 3.30 to 3.66. The pH decreased with increasing week of storage indicating acidity in orange juices. The use of sodium benzoate, sodium metabisulphite and potassium sorbate as preservatives significantly influence the pH of orange juice. The pH of samples was stable throughout the first and second week of storage.
Procedure The aim of this experiment was to determine how variations in the amounts of calcium carbonate would affect the amount of carbon dioxide produced within the time frame of one minute. By measuring the amount of carbon dioxide produced, the changes in the rate of reaction could also be determined. By the end of the minute, the more carbon dioxide was produced, the faster the rate of reaction. Throughout the minute, the flask containing hydrochloric acid and calcium carbonate was swirled around in continuous, circular motions. At the end of the sixty seconds, measurements were read off the indicator lines on the measuring cylinder where the waterline sat.
The purpose of this experiment was to analyze the rate of the catalyzed decomposition of hydrogen peroxide in regard to the effects of concentration and temperature. 2H2O2 (l) —I-—> 2H2O (l) + O2 (g) In part one of the experiment, catalyst KI was added to varying solutions of 3% hydrogen peroxide and DI water and the composition of hydrogen peroxide was observed. This was observed by collection the volume of oxygen gas produced during the decomposition, and measuring its volume. From that, volume of oxygen gas produced was plotted against time and a linear least square fit line was generate. From the line equation, rate was derived, rate is equal to the slope of the line.
Hypothesis: If one-day pinto bean seedlings are soaked in a water solution, 1% NaCl solution, and 3% NaCl solution, the seedlings exposed to higher sodium concentrations will have decreased cellular respiration rates. Treatments: This experiment involved three treatments and a control. The goal of the experiment was to see how different levels of NaCl affect the rates of cellular respiration in day-old pinto bean seedlings. In this experiment the rate of cellular respiration was measured by the amount of CO2 in ppm per gram of substance produced by a given treatment group or the control over the course of ten minutes. CO2 levels were measured using a CO2 sensor.
Chapter 1 Introduction 1.1 Background Disinfection is applied in water as well as wastewater treatment as a finishing step so as to destroy pathogens but the cause of concern regarding the disinfection process is the formation of disinfection byproducts (DBPs). Natural organic matter (NOM) in water has been considered as the predominant DBP precursors. Disinfectants are powerful oxidants that oxidize the organic matter present in water forming DBPs. Chlorine, ozone, chlorine dioxide, and chloramines are the most common disinfectants used nowadays and each produces its own suite of chemical DBPs in finished drinking water (Richardson, 2003). DBPs so formed pose a threat to human health
Moderate heating of the solution for a period of time is allowed to obtain a wet gel (Appendix figure 24). The wet gel may not look fully solid depending on the composition of the active added into the ethylene glycol. When all the active ingredients were dissolved in the ethylene glycol, the solution turned color from a clear red solution to a darker reddish brown color. The wet gel was observed to be slightly reddish brown in color. Before moving on to the formation of gel process, the magnetic bars were removed from all the samples.
The lab testing consists of investigating the rate of oxidation of Acid Sulfate Soils with variant temperatures. Since the transformation from PASS to AASS involves a significant pH drop to approximately one, rate of reaction and time was measured until the pH levels in the reaction even out at a low pH of approximately one. Appendix A & B demonstrate the oxidation reaction trials for each temperature over time, with pH levels recorded once every second. The time when the data stopped recording was determined when either the reaction had finished, or the time exceeds twelve minutes. This time limit was set due to a constricted time allowance of experiments.
The final volume was recorded. A pH probe connected through Microlab was calibrated using buffer solutions of pH 4.00, 7.00, and 10.00. The calibrated pH probe was used in order to measure the pH of the titrated solution of the unknown weak acid. These same steps were repeated except 2 mL of the strong base were titrated into the weak acid solution instead of 4 mL. This process was repeated 10 times.
2.5.7 Sulfur Sulfur content in biodiesel is limited to 15 ppm maximum by ASTM D6751.Therefore, it is important to know the original feedstock sulfur content since it can contribute to biodiesel sulfur content. The determination of sulfur in the feedstocks was done using ASTM D7039, Standard Test Method for Sulfur in Gasoline and Diesel Fuel by Monochromatic Wavelength Dispersive X-ray Fluorescence Spectrometry . Sulfur analyzer manufactured by X-Ray Optical Systems Inc.is used to measure the amount of sulfur. The value of sulfur in Jatropha oil is 3.5 (ppm) in accordance with ASTM D7039. 2.5.8 Phosphorous, Calcium, and Magnesium: ASTM D6751 requires phosphorous in biodiesel be limited to 10 ppm (0.001 % mass maximum) and the combined amount