To find the weight of the unknown the weight of the empty round bottom flask was subtracted from the weight of the round bottom flask containg the unknown. For the phthalic acid crystallization, students should calculate the % recovery. Extra care should be taken when lowering the temperature of a beaker to avoid this issue. Extract the unknown solid component of panacetin, which was weighed to be 0. Then after the filtration I was left with sucrose isolated, and then a substance containing aspirin and the unknown all mixed in with dichloromethane.
If the formula used in calculating molar mass is the molecular formula, the formula weight computed is the molecular weight. When heated to decomposition it emits toxic fumes. The aspirin was then separated with the help of sodium hydroxide to isolate the unknown. When calculating molecular weight of a chemical compound, it tells us how many grams are in one mole of that substance. Please read for more information.
During the war, a team including and developed a synthesis in Britain. Now we had to get our unknown substance out of the organic layer that was mixed with dichloromethane. Subject:Experiment 2: Extraction and Evaporation. The final product of one component, aspirin was. These applications will - due to browser restrictions - send data between your browser and our server. Bulletin for the History of Chemistry. I do not remember even seeing a streak above our second spot on the gel plate for the unknown, so this means we may not have spotted enough of the solution on the plate.
Referring to Table for the boiling point of pure benzene, the boiling point elevation is 81. The filter paper weighed around. Explain in detail how you determined it, comparing the data you obtained with known values. After allowing the aqueous mixture to cool the aspirin was collected by means of vacuum filtration and the weight was recorded, which was previousy mentioned. Everything looked to be dissolved, however my percent recovery proves to me that I was very close, just not close enough to get a within the desired sucrose range.
It was hard to tell if there some of the streaks actually had spots in them or not, so we may have missed on what should have been a third spot above the acetaminophen spot on our gel plate. So in theory I believe that we would have a more basic substance rather than an acidic one. The percentage by weight of any atom or group of atoms in a compound can be computed by dividing the total weight of the atom or group of atoms in the formula by the formula weight and multiplying by 100. Actinilide and Phenacetin can be converted to salts by Sodium Hydroxide. Once we dissolve the salt, our unknown solution will be left behind.
If the valve of the seperatory funnel is not properly sealed when initially pouring in the mixture there is a chance that some of the mixture will be lost. This was probably caused not by a mathematical error, but most likely by myself. Such as; different boiling points, melting points and their solubility properties. However, there is a suspicion that this bottle may be counterfeit, not containing the chemicals that it should. Once we extracted this solution, we were left with two different layers. We know the substance has to be Phenacetin or Acetanilide. Generally, it is made up of sucrose, aspirin and an unknown component, either acetanilide or phenacetin.
Aspirin - separatory funnel separate two liquids based on density ; vacuum filtration separate solid from liquid 3. Wear Chemically resistant Lab Aprons at all times in the lab. Capillary tubes will be used to spot the samples of 1-asp, 2-ace, and 3-unk on the coated side of one plate. This step was repeated once; the seperatory funnel was then placed into the lab hood and through a metal ring holder. However, once we subtract the filter paper we only have. To do this a chemist can also asses the differences between acidic and basic substances when they are added to water soluble mixtures. We use the most common isotopes.
The lid of the jar was screwed on and the plates were allowed to sit in the jar until the ethyl acetate rose to about 2 cm from the top of the plate. Panacetin should be made up of about 50 percent of the unknown component that we previously separated out of Panacetin for testing. After stirring the solution thoroughly, some solid is formed solid sucrose and liquid. This site explains how to find molar mass. These relative weights computed from the chemical equation are sometimes called equation weights.