The success of extracting each compound out of the solution can be seen in the IR graphs for each substance. For ethyl 4-aminobenzoate, the N-H, C=O and C-O are distinguishable in their proper wavenumber positions. The amino N-H stretch was found between 3224 cm-1 and 3423 cm-1. The C=O was found at 1681 cm-1 and the C-O was at 1280 cm-1. The IR for benzoic acid also displays its significant bonds, O-H and C=O. The O-H was between 2566 and 3222 cm-1 and the C=O stretch was found at 1685 cm-1. The IR for 9-fluorenone did not show any significant bonds except for at 1681 cm-1, the C=O stretch.
To separate 4-aminobenzoate into an aqueous layer, HCl was added to protonate the NH2 side group and form a salt, creating its high solubility in water and low solubility in ether. This allowed the immiscible layers to be distinguished. The addition of NaOH after pouring out the aqueous solution allowed for aminobenzoate to reform from its salt form. However, while inverting the funnel to vent before pouring out the layer, some solution leaked out of the cap, which may account for the loss of completely recovering this compound because only 39.3% of ethyl 4-aminobenzoate was recovered.
For the recovery of benzoic acid, NaOH was added to convert the carboxylic acid of the benzene to the water-soluble benzoate anion, which dissolves in the aqueous NaOH solution while the non-acidic impurities remain in the organic phase. After separating the aqueous layer into an Erlenmeyer flask, the basic solution of sodium benzoate was acidified by washing it with HCl and filtering it with DI water. This compound had to most significant recovery of 46. 3%, but some may have been lost through the leakage of the previous extraction.
The Essay on The Ozone Layer Earth Air Compounds
The Ozone Layer In environmental science the green house effect is a common term for the role water vapor; carbon dioxide and ozone play in keeping the earth's surface warmer than it would normally be. The atmosphere is primarily transparent to infrared radiation from the sun, which is mostly absorbed by the earth's surface. The earth being much cooler than the sun, remits radiation most strongly ...
The neutral compound left in the organic layer was the most difficult to extract. It’s IR graph does not properly show a pure substance, but many errors were involved in its extraction. Since this was the last remaining compound in the organic layer, an anhydrous drying agent, Na2SO4, was used to bind to water and remove it from the organic liquid. Not much of the organic layer was left over, but more and more of the drying agent had to be added because the solution kept forming clumps, so a large amount of water must have been present. More organic solvent should have been added also, but at the time, it was not, so some product may have been lost by its absorption on the drying agent. After 10 minutes, the drying agent was washed, and the ether solution was transferred to a new flask to be recrystallized on a hot plate. Recrystallization involves dissolving an impure solid in a hot solvent and destroying the impure crystal lattice, then returning it to a solid by precipitating in a cool solvent and producing a purer crystal lattice.
However, bonds appear in the O-H region of the IR graph and show that this compound was still impure. This may have happened because the solution should have been dried longer with the drying agent, or the recrystallization happened too fast because it was at a hot temperature. Slow cooling is supposed to promote the formation of pure crystals because the molecules of the impurities, that do not fit well into the newly forming crystal lattice, have time to return to the solution. However, the rapid crystal formation must have trapped the impurities because the lattice grew so quickly that the impurities were surrounded by the crystallizing solute. This is why 9-fluorenone seemed impure and how too much drying agent and leakage during filtration may have contributed to its 27% recovery.
The Essay on Determine The Macromolecules Present In An Unknown Solution
Every living thing is dependent on large complex molecules, known as macromolecules. The objective of this lab was to correctly identify which macromolecules the unknown solution was comprised of using various substances as experimental controls. There are four major types of biological macromolecules – carbohydrates, lipids, proteins, and nucleic acids – made up of elements such as ...
