Recrystallization Of Pure Phthalic Acid

An Erlenmeyer flask was used to accommodate the largest volume of recrystallization solvent calculated and was cooled in an ice bath to increase the yield of crystals. The solid was collected by vacuum filtration and washed with a small amount of ice water. The product is then dried to a constant mass by use of an oven and weighed. A small amount of the unknown was compared to two samples of acetanilide and phenacetin for a melting point range to determine the identity. The temperature of the unknown was recorded when the first trace of liquid can be seen and when the unknown was completely liquid.

The unknown sample was then heated in boiling water in step 5. The reason for heating the

The recrystallization technique utilizes the ability of a compound to dissolve within a hot solvent and produce a solution. As this solution cools, the solute reforms without impurities in a crystal lattice structure.1 For this to work properly, an appropriate solution that will not dissolve the solute at low temperatures, but will at high temperatures, must be used.1 There is no single solvent that will work well for every solute’s recrystallization; different solvents are better suited for some solutes than others.2 Some impurities that do not dissolve within the solvent can be filtered out while the solution is still hot, while other impurities that readily dissolve within the solvent shouldn’t recrystallize with the pure substance (as they are not concentrated enough to

The product was placed in a Craig tube and several drops of hot (100°C) solvent (50% water, 50% methanol, by volume) was added and heated until all of the crystals dissolved. The Craig tube was plugged and set in an Erlenmeyer flask to cool. Crystallization was induced once the mixture was at room temperature by scratching the inner wall of the tube. It was then placed into an ice bath for ten minutes until crystallization was complete. The tube was then

Solub. Or Reaction w/ hot H20: no change observed from the cool water and is soluble

The first step is the separation of the solid crystals back into separate ions, a positive ammonium ion and a negative nitrate ion. The break these ionic bonds requires a lot of energy which means heat must be taken from the surrounding water. The second step the water molecules, which are H2O, are attracted to the ions and attach themselves to the ions. The second step actually causes heat to be produced to the surrounding liquid mixture. .Even

17) Pour a small amount of the hot solvent into the flask containing the solid.

The product was then suspended in 2 ml of water with a stir rod in a 50 ml Erlenmeyer flask and heated to boiling. Water was added in one milliliter increments until all the product was dissolved (18 ml added total). The saturated solution was allowed to slowly cool, and gradual white crystal formation was observed. Recrystallized product was collected once more by suction filtration with the Hirsch funnel once crystallization ceased. Collected product dried on a watch glass for a week, weighed 0.14 g (1.2 mmol), and the melting point was 139°-141°

Upon the addition of water, it was noted that a layer separation occurred and the water layer remained on top, with the 2-methylphenol layer on the bottom layer. Then, conversion calculations were performed to determine the appropriate amount of 3M NaOH to be added to the 2-methylphenol solution. From the calculations, it was determined that 1.08 mL were to be added. 3M NaOH itself was a cloudy solution in appearance and upon the addition of 3M NaOH to the 2-methylphenol solution, it was noted a color change occurred and it became a yellow-green solution. Following this, the same calculations used previously, were used to determine the appropriate amount of sodium chloroacetate, which was found to be 0.38 g (3.26 mmol). Sodium choloroacetate was a white, crushed solid that was then combined with 1 mL of water and was swirled until the sodium chloroacetate completely dissolved. This sodium choloracetate solution was then transferred to the 2-methylphenol solution by the use of a medicine

To tube 2 and tube 3 a boiling chip is added. The two tubes are boiled to remove any residual ether. Next, the tubes are cooled to room temperature and placed into an ice bath to allow for crystallization. The solution is then removed from the solid in each tube and discarded. To tube 2 and 3 ~0.5 ml of H2O is added for recrystallization, the tubes

Solvent – A solvent is the liquid that dissolves the solute to create the solution.

Once cooled, the mixture was then transferred to a separatory funnel using the funnel while avoiding adding the boiling chip. 10 ml of water was then added to the mixture. The mixture was gently shaken and the phases were allowed to separate. The funnel was then unstopped and the lower aqueous phase was drained into a beaker. 5 ml of 5% aqueous NaHCO3 was added and then shaken gently. A great deal of caution was taken into consideration because of the production of carbon dioxide gas which caused pressure to develop inside the funnel. The pressure needed to be released so the funnel was vented frequently. The phases were allowed to separate and the lower aqueous phases was drained into the beaker. After draining, 5 ml of saturated NaCl was added to the funnel and then shaken gently. Once again, the phases were allowed to separate and the lower aqueous phase was drained into a beaker. An ester product was produced and was transferred into a 25 ml Erlenmeyer flask. This organic product was then dried over anhydrous Na2SO4 to trap small amounts of water in its crystal lattices thus removing it from the product. Finally the ester was decanted, so that the drying agent was excluded from the final product.

Crystals were collected in a Buchner funnel, washed with alcohol, then ether, then transferred into a sample tube for storage.

The proposed project inspired to put up multipurpose cooperative in Jovellar, Albay to produce charcoal briquettes out of coconut shells and agro forest wastes such as grasses, twigs and leaves. Charcoal Briquettes provide high quality of solid carbonized fuel that is easy to ignite a steady heat with low clean flame. It is deemed environmentally sound and sought to replace the traditional charcoal in the community which gives great threat to the environment that cause of cutting trees in

When charging the compound, heat is applied to substance AB which dissociate into separate A and B molecule/compound. The storage is facilitated by using certain inhibitors that control the reverse reaction. To release heat, the A and B components are reacted by removal of inhibitors, ultimately favoring the reaction, resulting in the formation of compound AB and releasing heat. During this cyclic process, when the reaction between A and B is prevented, the heat which can be stored due to chemical energy cannot be released. The adsorbent such as zeolite (see Figure 3) react with water thereby act as a sorptive storage material where adsorption of water