Isolation of Caffeine from Tea CHEM243A 2-23-11 Abstract: The purpose of this experiment was to isolate caffeine from a tea bag. Once isolated, the caffeine was purified using sublimation. The percent recovery was calculated to be 83.3%. The melting point of the original substance was 51ºC-139ºC. Since it was inaccurate, the melting point of another group’s sample was recorded.
The end result is that the cut, in addition to the ammonium salt (NH4Cl), remains in the freebase cocaine after the mixture has evaporated. The “rock” that is thus formed also contains a small amount of water. A spoon with a mixture of baking soda, cocaine and a small amount of water, when heated from below, small crack cocaine ‘rocks’ will begin to form in the mixture. A spoon with a mixture of baking soda, cocaine and a small amount of water, when heated from below, small crack cocaine ‘rocks’ will begin to form in the mixture. Baking soda is now most often used as a base rather than ammonia for reasons of lowered odor and toxicity; however, any weak base can be used to make crack cocaine.
Coconut water Touted for its rich electrolyte content, coconut water is great as a post-exercise recovery drink. The first entrants to the market were offered in Tetra Paks and were flash pasteurized. Pasteurization of coconut water involves heating it at 120 degrees for five seconds to kill any bacteria that may be present. The slightly whitish liquid in these little cartons has a vaguely coconutty flavor, but I've only ever been able to drink them ice cold. The new wave of "cold-pressed" juices are being sold in plastic bottles and are pasteurized using high pressure processing (HPP), also called pascalization.
When the students arrived to the classroom, quickly they measured the mass of the eggs, and discussed about the solutions. This is a way to demonstrate osmosis. Experiment: In the experiment, students needed to fill four jars; two with distilled water, one with vinegar, and other one with syrup. One of the jars with distilled water was to remove the shell of the egg; this process had to be done two more times, since the students are using three eggs. Students need to put the eggs, after their shells have been removed, in the corresponding jars and leave them for two days.
4). As the teacher student relationship continues to be narrative it reveals itself like a banking system. Teachers are depositing information into the studentsâ€™ minds just as a depositor deposits into a bank account. Students are taking the information and memorizing it rather than connecting with it and knowing why they are given this information. â€œEducation thus becomes an act of depositing, in which the students are the depositories and the teacher is the depositor.
3. Calculate the mass of baking soda,NaHCO3 , and find the percentage of baking soda in the unknown mixture. ※ Data and observations (a) Table 1: Percent yield of Na2CO3 from baking soda Percent yield of Na2CO3 from baking soda Trial 1 Trial 2 Mass of flask + NaHCO3 95.12 g 93.45g Mass of flask 94.15g 92.03g Mass of NaHCO3 0.97g 1.42g Mass of flask + Na2CO3 95.01g 93.12g Mass of Na2CO3 (actual yield) 0.86g 1.09g Mass of Na2CO3 (theoretial yield) 0.61g 0.90g % yield of Na2CO3 140% 120% (b) Table 2: Percent of baking soda in Unknown Percentage of NaHCO3 in an unknown mixture # C Trial 1 Trial 2 Mass of flask + unknown mixture #C (before heating) 95.81g 94.85g Mass of flask 94.15g 92.03g Mass of unknown mixture (before heating) 1.66g 2.82 g Mass of flask + residue (after heating) 95.20g 93.80g Mas of H2CO3 (H2O + CO2) (after heating) 0.61g 1.05g Mass of NaHCO3 in the unknown mixture 1.65g 2.84g % of NaHCO3 in the unknown mixture 99.0% 101% ※ Calculations For table 1: Theoretical yield of Na2CO3 for trial 1
4). As the teacher student relationship continues to be narrative it reveals itself like a banking system. Teachers are depositing information into the students’ minds just as a depositor deposits into a bank account. Students are taking the information and memorizing it rather than connecting with it and knowing why they are given this information. “Education thus becomes an act of depositing, in which the students are the depositories and the teacher is the depositor.
In Pennsylvania Pepsi files off the self in the local Wal-mart and grocery stores. Pepsi was introduced in 1890’s but was not trademarked until 1903 and it has medical claims like to cure stomach problems. Pepsi is concentrated at first then water is added. Coca-cola was introduced in 1886 as a patent medicine. It claimed to cure whatever bothered you such as an addition to morphine, headaches, and impotence as well as more.
Spectrophotometric Determination of Benzoic Acid Concentration in Non-diet Soft drinks Abstract The concentrations of benzoic acid in non-diet soft drinks (sprite, 7-up and virgin lime) was determined using UV-Vis spectrophotometer. Experimentally, the benzoic acid acquired a λmax of 220 nm. By setting the photometric mode at 220 nm, sprite obtained 142.200 ppm, 7-up attained 170.425 ppm and 141.300 ppm for virgin lime. INTRODUCTION Non diet soft drinks are beverages that contain sweetener, carbonated water, flavouring agent and food preservative. Manufacturers of soft drink commonly used benzoic acid or sodium benzoate as food preservatives.
When using Benedict’s reagent, monosaccharides can be identified. Benedict’s reacts with double bonds connected to the oxygen atom in either the free ketone or aldehyde groups (which are the reducing sugars in saccharides) to reduce the copper sulfate in Benedict’s reagent (Harris-Haller 2014). When the substance is heated with Benedict’s reagent, an orange-red precipitate forms within the solution. There were 10 substances in all that we tested for. They were glucose, water, lemon juice, Coca Cola, egg batter, lemon-lime soda, diet lemon-lime soda, Kraft Italian dressing, skim milk and butter.