Specific Heat of a Metal Michael Diaz Ms. Zhort Performed: October 3, 2013 Due: October 24, 2013 Period: 1 Lab Partner: Rocco & Asha Objective: This lab was meant to teach us how to find the specific heat of a metal sample. Materials: * Specific heat set * Balance * Thermometer * Tap Water * Hot plate * Polystyrene cup and a lid * Stirring rod * 250 mL beaker * String (about 15 cm) Procedure: 1. Fill a 250 mL beaker approximately half full of water. Place the beaker of water on a hot plate. Begin heating the water to the boiling point.
Upon the reaction’s completion, the solution was filtered using an aspirator (filter and vacuum) so that all of the remaining undissolved aluminum waste was removed from the solution. Once filtered, the filtrate and a small amount of excess water (used to rinse filtrate) were placed in another 250 mL beaker. Next, a 20 mL sample of 6 M sulfuric acid was added to the filtrate with the excess of water. A solid began to form, so the solution was stirred and placed on a hot plate to dissolve the precipitate that was formed. Once the solution was heated and stirred for a few minutes, a similar filtering process was used to remove whatever remaining insoluble solid was in the solution.
The mixture was decanted again in to the same beaker. Next, we added boiling chips to the liquid and evaporated the solvent over the hot plates under the hood. After the solvent was evaporated and the flask was cooled, we used a spatula to remove a small amount of the crude product and took its melting point. We determined the melting point range of the sample to be 43.0-46.0 degrees Celcius.The crude product was yellow colored when it was warm and orange in color when cooled and sticky. We then recrystallized our sample using 5 ml of warm acetone that was heated on a hot plate under a hood.
Put the stopper in the flask in order to drive out all the air and any excess water. Work the stopper gently into the flask, so that it is firmly seated in position. Wipe any water from the outside of the flask with a towel and soak up all excess water from around the top of the stopper. Again weigh the flask to the nearest milligram. Having the density of water and the temperature of water, you should be able to determine the volume of the flask very precisely.
3. Using a retort stand and a burette clamp the burette was set up. 4. It was ensured that the stopcock was shut, and then using a funnel the burette was filled and then drained to make sure that the NaOH solution wouldn’t get contaminated. 5.
4. Fasten the thermometer to the holder. 5. Submerge the tube half way into the beaker of water that is on the hot plate. Since a beaker is being used, stirring the water consistently is necessary.
Once it started boiling the temperature was taken and it was 102 degrees Celsius. After the first results were recorded and beaker C was cleaned out and put away, beaker B (5 grams of salt) was placed onto the hot plate. As beaker b started boiling the temperature was recorded at 100.8 degrees Celsius. The results were then written, the beaker was cleaned out, and then put away. The
8. Use tongs to move the beaker from the hot plate to the lab bench. Wait until the beaker cools down. 9. Filter the solution with a funnel and a piece of filter paper.
Wait for the bubbling to subside between additions so that the reaction does not overflow the flask. 6. When all the acetic acid has been added, swirl flask or stir for two minutes with a glass stirring rod. 7. When the solution is completely calm, move the flask to a hot plate and heat it to boiling.
To facilitate the viewing and measuring of the very flat cylinder we need to take a pizza pan of water and fill it with water to cover the entire surface. Once it is filled we need to sprinkle some lycompodium powder onto the surface of the water using your small spatula. This will be used to outline our oil spot when we place one drop of the diluted solution onto the water surface. One other thing we will do to make the experiment more visible is to add a few crystals of potassium permanganate to darken the water. We are also going to dilute the Oleic acid down to a 500:1 ratio.