Indemnify an unknown compound using mixture melting points. Introduction Energy is needed to be applied to a solid compound in order to changes its state point of a compound. The actual purpose of the experiment is to determine the measurement and the melting points of the benzene and mandolin acid and various mixtures of Mandalay and benzene acid, and an unknown compound. In addition to that, later we will be able to indemnify the unknown compound by comparing the melting points with the various compounds. Materials needed to do the experiment 1.
Bucket of Ice 2. Benzene acid 3. Capillary tube 4. Mandolin acid 5. Rubber band 6. Vegetable oil 7. Unknown compound 8. Bunsen burner . Gram scale 10. Mortar and a piston 11. Mixture of benzene and Mandolin acid 12. Micro-spatula 13. Thiele tube 14. Thermometer 15. Watch-glass Procedure The melting point will be observed with the use of a Thiele tube melting point apparatus. Primarily, using a mortar and its piston, the benzene acid is ground (crushed) into fined powder. Two milliards of it is measured and placed into a watch glass by which grams scale.
From that point, a capillary tube is loaded with the fine powder by tapping the open end of the tube into the glass plate which the powder is located. Therefore, locate the powder at the bottom tube y tapping the closed and of the tube on the table top. When you complete this, a Thiele tube melting point is apparatus is set up. The apparatus is set up by pouring vegetable oil from the bottle into the Thiele tube. Next, the benzene is packed into the capillary tube, which is attached to the thermometer, and is held tightly by the rubber band.
The Thiele tube is heated by using a Burses burner. The tube then is heated rapidly at 110 degrees Celsius and then slowly by one or two degrees Celsius per minute, because the melting point of the benzene acid is 122-123 degrees Celsius and rapidly the heating rate results in inaccurate melting mint measurement. The temperature at which the first bash is measured is then recorded as its melting point. After recording the results, the bucket of ice is used to cool down the Thiele and capillary tube to room temperature and the capillary tube is discarded.
That procedure is repeated to measure the melting point of the 2 milliards of mandolin acid just as it was done for the benzene acid. Four mixtures of benzene and mandolin acids are obtained. Mixture 1 will have a composition of 80% benzene acid and 20% mandolin acid while mixture 2 will contain 60% benzene acid and 40% of mandolin acid. On the diverse, mixture and 4 will have the opposite of mixture 1 and 2. Using a marker, label the capillary tube for each mixtures on a horizontal line for each tube, and it must be at least three centimeters above the surface of the oil when it is heated because the oil does expand.
Each capillary tube is loaded with mixtures labeled on them. After this phase, place capillary tubes loaded with the mixture 1 and 2 into the Thiele tube apparatus and heat the tube rapidly to 80 degrees Celsius. At this process, slow the rate of heating to 1-2 degrees per minute. Record the temperature when the first crystal in the mixture is beginning to melt, and cool he apparatus to 80 degrees Celsius right after, using the bucket of ice. Repeat this procedure to record the measurement of melting points for mixture 3 and 4 as described before for mixtures 1 and 2.
Obtain the unknown pure compounds, unknown mixtures of benzene and mandolin acids in this case and pulverize the unknown mixture into a fine powder form, using a mortar and a piston. Load the powder into a capillary tube, and place it onto the Thiele tube. Heat the compound to record its orientation melting point. After doing this, cool the tube to 15 degrees Celsius below its orientation melting point, using a bucket of ice, ND prepare a new sample. Measure its melting point and identify the mixture by comparing its melting point with the melting points of the various Mixtures 1-4.
Table 1: Compound and mixtures vs.. Melting point Compound and mixtures Melting point in degrees Celsius Benzene acid Mandolin acid Mixture 1 Mixture 2 Mixture 3 Mixture 4 Unknown mixture (compound) 1180 1190 1000 820 980 850 920 Graph 1 : Mixtures vs… Melting point Conclusion The experiment was concluded on September 18th, 2013 in a lab at College. The observed melting points of the benzene and mandolin acids were lower than heir actual melting points. Therefore, there must have been crusts in the oil used for the Thiele tube apparatus.