The purpose of this experiment was to isolate caffeine that is found in tea by using the techniques of extracting, separating, drying, and sublimation. Elizabeth Ping November 22, 2 Observations and Calculations: Mass of tea bag 2.
The predetermined masses provided by the Lipton Tea manufacturers are accepted as the experimental measurements of both tea and caffeine. The approximate weight of an individual Lipton tea bag is 2. In an experiment using 2 tea bags, mg is the expected yield of caffeine to obtain.
A 50 mL beaker, along with 2 boiling stones, was weighed in advance with a total mass of To extract caffeine, the heated tea solution, along with 5 mL of methylene chloride, was poured into an isolated separatory funnel and inverted to mix the solution completely.
Due to the reaction, pressure built up inside the funnel, requiring the stopcock to be opened to release excess gas following each inversion. Once settled, the solution separated into 2 layers: The tea separated above the methylene chloride because while the density of water is 0. Between the two layers sat small bubbles or possible emulsions that restricted the amount of methylene chloride that could be extracted.
In doing so, the volatile methylene chloride began to evaporate into the surroundings due to the increased room temperature. The remaining solution was heated briefly until the volatile solvent evaporated, leaving behind solid caffeine.
When weighed, the beaker, stones, and caffeine rendered a total mass of The difference in mass between the initial weight of the beaker and the final product was then the actual yield of caffeine, 0.
In comparison to the theoretical mass, the experiment provided The solid caffeine product was run through an Infrared Spectrometer that uses bond energies to identify chemical compounds. The spectrometer produced a graph based on measurements of photon energy within a frequency range between and Hz.
Individual spikes on the graph indicate the unique bond energies of certain functional groups. For example, the photon energy spike visible around the Hz frequency represents amine and amide group apparent in caffeine.
The other important spike appears around Hz and Hz. This spike represents the alkene portion of the caffeine molecule. Using these individual spikes in photon energy, the infrared spectrometer predicts the composition of the compound present. The spectrometer predicted the probability that the sample produced was caffeine to be out of This value has no relation to the purity of caffeine.
The mass of caffeine from 2 Lipton tea bags was only The error in yield results from a number of unavoidable experimental flaws. The first flaw originates from the reaction between gallic acid and sodium carbonate. Although the conversion of gallic acid is necessary for the reaction of caffeine and methylene chloride to occur, the phenol anion byproduct of this reaction is responsible for necessary error .Isolation of Caffeine from a Tea Bag Objective: In this experiment, caffeine is isolated from a tea solution.
Caffeine is an analgesic drug that increases the heart rate. It exists naturally in especially tea and coffee. Caffeine constitutes as much as 5% by weight of the leaf material in tea bags. Molecular structure of caffeine Introduction:4/5(4).
4) A possible explanation for a lower than expected melting point observed for caffeine that is less than °C could be due to impurities within the caffeine sample. Elizabeth Ping | November 22, | 3 References: "Isolation of Caffeine from Tea".
Experiment 1: Isolation of Caffeine from a Tea Bag Objective: To extract caffeine from tea powder using polar - nonpolar solvent extraction technique.
Theory: Caffeine is 5/5(24). Isolation of Caffeine from Tea Leaves Introduction Caffeine is a member of the class of compounds organic chemists call alkaloids.
Alkaloids are nitrogencontaining basic compounds that are found in plants. They usually taste bitter and often are physiologically active in humans. Isolation of Caffeine from Tea In this laboratory exercise we will isolate Caffeine from Tea and then derivatize it to form Caffeine Salicylate.
The purpose of this last step is to generate a compound whose Weigh the tea bag or tea leaves. 2.
|Search form||It can be isolated from natural sources like tea leaves, cola nuts and cacao beans. Caffeine is an alkaloid, and more specifically, a member of the methlxanthines.|
Heat mL of water in a mL beaker to 85oC - . Experiment 1: Isolation of Caffeine from a Tea Bag Objective: To extract caffeine from tea powder using polar - nonpolar solvent extraction technique. Theory: Caffeine is 5/5(24).