Lab Report on Density Measurement

mental home 1. 1 Background of the look into fortune tautness describes how heavy an object is. be by the Greek letter ? , pick up as rho, tightfistedness is a grassroots yet important physical space of discipline. For a bulk body without write up its existing pores and voids, assiduity is equal by the ratio of its fate and intensity level. It is aband id by the equation ? = loudness playscript 1. The SI unit of engrossment is kg/m3. However, its CGS units, g/cm3 or g/ mL, atomic number 18 the most normally utilize virtuosos in the research lab. The conversion is given by 1 gcm3=1gmL= vitamin C0 kgm3 1.The concentration of a homogeneous unstable is overly defined by the amount of thr unmatchable per unit stack. runniness is usually engrossed in a container, so its volume is relative to the volume of its container 2. There are various instruments that are employ to accurately appreciate the tightness of substances the most commonly used are the densit ometers, pycnometer and hydrometers 3. In this look into, the assiduity of selected politic tests will be mensurable using a pycnometer. 1. 2 Objectives of the Experiment 1. To determine the assiduity of low boil point smooth samples by quantity their pack at controlled volume 2. o determine the immersion of aluminium oxide by metre the mass and volume of diversely shaped aluminum oxide swellings and 3. to equivalence the assiduousness calculated from the given samples with the commonplace density at path temperature. 1. 3 conditional relation of the Experiment At the end of the experiment, the laboratory performer is expected to learn the pursuit 1. the density of selected liquids and material at a given temperature and 2. the proper method of measuring the volume and consequently the density of irregularly shaped objects using water shimmy method.REVIEW OF RELATED LITERATURE assiduity is bingle of the most important and commonly used physical propertie s of matter. It is an intrinsic property which is equal by the ratio of a matters mass to its volume 3. tightfistedness was purportedly discovered by the Greek scientist Archimedes in an unusual circumstance. According to stories, ability Hiero of Syracuse asked Archimedes to determine whether his new gratuity is made of pure notes or not. It was seemingly impossible to identify the aureate fortune that composed the go past because chemic analysis was still unstudied in those times.One day, when Archimedes was enjoying himself to a bath, he observed that the barely he went down the tub, the less(prenominal)(prenominal)er he weighed and the higher the water level blush up. He then came to the realization that he could determine the ratio of the mass of the crown and the volume of water displaced by the crown, and differentiate it to the place measured from the pure gold sample. Hence, density and the principle behind it were revealed 4. tightness is dependent on many di visors, one of which is temperature. It specifically decreases with increasing temperature.This is because an objects volume undergoes thermal expansion at increasing temperature while its mass corpse un reassignd. This results to a decrease in density 1. When matter undergoes a transformation to a different phase, it undergoes an abrupt change in density. The transition of molecules of matter to a less random form, say from gas to liquid or from liquid to solid, causes a drastic increase in the density. However, there are substances which behave differently from this density-temperature descent, by which one example is water. The greatest density achieved by water molecules are at 4C.At temperatures higher or lower than 4C, its density slowly decreases. This makes ice less dense than water, a property not commonly exhibited by other liquids 3. methodology 3. 1 textiles A. Pycnometer, 25-mL B. Graduated cylinder, one hundred0-mL C. Graduated cylinder, 250-mL D. Beaker, 250-mL E. low boiling point liquids (acetone, 70% response ethyl group alcohol, 70% solution isopropyl alcohol), 30 mL F. Distilled water G. Two sets of alumina balls (small cylindrical, large cylindrical and large globose balls) H. Analytical proportion ship 3. 2 ascertain the pot of a 25-mL perspicuous 5 A.cautiously clean and dry the pycnometer. B. Weigh the free pycnometer and its stopper in the balance beam and record the mass. C. Fill the pycnometer with the liquid sample up to its brim, and insert the stopper carefully. clean off any excess unruffled on the sides of the pycnometer with a clean textile or tissue. D. Balance and record the mass of the filled pycnometer plus the stopper. E. Empty the circumscribe of the pycnometer in a clean beaker. F. imbibe three trials for each liquid. 3. 3 Determining the Mass and strength of aluminium oxide swellings 5 A. notice the mass of each alumina ball in the balance beam. B.Add distilled water to the have cylinder and rec ord its initial volume. C. Carefully drop an alumina ball to the receive cylinder and measure the new volume. Do this by slightly tilting the cylinder and gently sliding the ball to its side. D. Use the 250-mL graduated cylinder for small cylindrical alumina balls while the 1000-mL cylinder for the large cylindrical and spherical alumina balls. E. Do the comparable procedure for the two sets of alumina balls. 3. 4 figure the density of Liquid 5 A. work out the mass of the liquid by reckon the difference between the recorded mass of the pycnometer when empty and filled with liquid.B. Calculate the density of the liquid by dividing its obtained mass by the volume indicated on the pycnometer. C. Record and equate the resulting density of the liquid with the measuringised place at room temperature. 3. 5 Calculating the concentration of Alumina Balls 5 A. Compute for the volume of the alumina balls by subtracting the initial volume from the final volume of water in the gradua ted cylinder. B. Calculate for the density of the alumina balls by dividing the measured mass by the volume. C. Record and compare the resulting density of the alumina balls with the standard value at room temperature. 3. Data and Analysis card 1. The mass of the four 25-mL liquid samples measured in three trials Liquid Volume (mL) Mass (grams) 1ST trial 2nd Trial 3RD Trial weewee 25. 0 25. 244 25. 348 25. 359 Acetone 25. 0 20. 131 20. 147 20. 163 ethyl radical inebriant 25. 0 22. 313 22. 330 22. 337 Isopropyl alcoholic beverage 25. 0 22. 025 22. 035 22. 049 give in 2. The volume and mass of the two sets of alumina balls Alumina Ball (based on Size) fall 1 organise 2 Volume (mL) Mass (grams) Volume (mL) Mass (grams) belittled cylindrical 2. 0 5. 813 2. 0 5. 742 gigantic cylindrical 8. 5 24. 042 9. 5 23. 42 giant spherical 10. 0 22. 975 9. 0 19. 747 Table 3. reckoning of density of the four liquid samples Liquid Density (grams/mL) maiden Trial 2ND Trial tertiary Tr ial Water 25. 244 ? 25 = 1. 00976 25. 348 ? 25. 0 = 1. 01392 25. 359 ? 25. 0 = 1. 01436 Acetone 20. 131 ? 25. 0= 0. 80524 20. 147 ? 25. 0 = 0. 80588 20. 163 ? 25. 0 = 0. 80652 Ethyl alcoholic beverage 22. 313 ? 25. 0= 0. 89252 22. 330 ? 25. 0= 0. 89320 22. 337 ? 25. 0= 0. 89348 Isopropyl Alcohol 22. 025 ? 25. 0= 0. 88100 22. 035 ? 25. 0= 0. 88140 22. 049 ? 25. 0= 0. 88196 Table 4. advisement of density of the alumina ballsAlumina Ball (based on Size) Density (grams/mL) Set 1 Set 2 subatomic cylindrical 5. 813 ? 2. 0 = 2. 9065 5. 742 ? 2. 0= 2. 8710 Large cylindrical 24. 042 ? 8. 5= 2. 8285 23. 942 ? 9. 5= 2. 5202 Large spherical 22. 975 ? 10. 0= 2. 2975 19. 747 ? 9. 0= 2. 1941 Table 5. The mean value of the density calculated from the four liquid samples Liquid Mean Value (g/mL) Water 1. 00976 + 1. 01392 +1. 014363 =1. 01268 Acetone 0. 80524 + 0. 80588 + 0. 806523 =0. 80588 Ethyl Alcohol 0. 89252 + 0. 89320 + 0. 893483 =0. 89307 Isopropyl Alcohol 0. 88100 + 0. 88140 + 0. 881963 = 0. 8145 Table 6. The mean value of the density calculated for the alumina balls Alumina Ball (based on Size) Mean Value (g/mL) depressed Cylindrical 2. 9065 + 2. 87102 =2. 8888 Large Cylindrical 2. 8285 + 2. 52022 =2. 6744 Large Spherical 2. 2975 + 2. 19412 =2. 2458 Average 2. 8888 + 2. 6744 + 2. 24583 =2. 6027 RESULTS AND DISCUSSIONS The table to a lower place shows the obtained densities of the samples in four decimal places. Table 7. Summary of data-based densities of the samples Liquid/ secular Density (g/mL) at 25C Acetone 0. 8059 Alumina 2. 6027 Ethyl Alcohol 0. 8931Isopropyl Alcohol 0. 8815 Water 1. 0127 Table 8. authorized value of the density of certain materials at 25C 6 Liquid/Material Standard Density (g/mL) at 25C Acetone 0. 7846 Alumina 2. 7300 Ethyl Alcohol 0. 8651 Isopropyl Alcohol 0. 8493 Water 0. 9970 the true of the result, or the agreement of the experimental value to the original value, is defined by its office error. An experimental result with a percenta ge error less than 5% is considered to be accurate. This indicates that the laboratory procedure performed in obtaining the say result is scientifically reliable 7.The bordering table shows the calculation of the percentage errors of the densities obtained from the experiment relative to the accepted values represented in Table 8. Table 9. Calculation of the percentage error of the experimental densities of the samples Liquid/Material Acetone 0. 7846 &8212 0. 80590. 7846 ? 100 = 2. 643% Alumina 2. 7300 &8212 2. 60272. 7300 ? 100 = 4. 663% Ethyl Alcohol 0. 8651&8212 0. 89310. 8651 ? 100 = 3. 237% Isopropyl Alcohol 0. 8493&8212- 0. 88150. 8493 ? 100 = 3. 791% Water 0. 9970 &8212 1. 01270. 9970 ? 100 = 1. 550%Table 9 shows the percentage errors of the experimental densities computed from the samples. The values indicate that the experimental densities of acetone, alumina, ethyl alcohol, isopropyl alcohol and water at 25C are within 5% error from accepted values, thereby implying th at these results are accurate and the procedure used in performing the experiment is correct, consistent and reliable. Small disagreements in the values of experimental and accepted densities can be accounted to factors that could slightly change the density of a material, in which one of these is temperature.The actual room temperature was not actually measured due to personal negligence, and was scarcely assumed to be 25C. Thus, the standard values that are used to compare with the results might be not be the most appropriate ones relative to temperature. other factors which could lead to slight discrepancies in density could be the unavoidable arrogant errors, oddly instrumental and human errors. CONCLUSION AND tribute In general, the experimental densities of all the samples used are significantly close to the standard densities at 25C. Thus, the laboratory rocedure was through correctly and consistently. Small deviations of the results from the accepted values might be du e to systematic errors. One of which can be caused by the lack of precision of the analytical balance beam. Human errors such as chimerical or inconsistent readings and interpretations of results might similarly cause these slight disagreements between the standard and experimental values. It is recommended to future laboratory performers to measure the actual room temperature before, while and afterward conducting the same experiment, to make sure that the temperature is unbroken all throughout.Temperature is a vital factor that could affect the results of the experiment. Hence, this must not be neglected. Nevertheless, the method of using pycnometer to measure the density of the liquids and water displacement method for the irregularly shaped solids yields accurate and reliable results. REFERENCES 1. Gallova, J. (2006). Density determination by pycnometer. Retrieved July 8, 2012 from Comenius University of Bratislava at http//www. fpharm. uniba. sk/fileadmin /user_upload/engli sh/Fyzika/Density_determination_by_pycnometer. pdf 2.University of Massachusetts Boston, College of Science and mathematics (2005). Measurement of Density and Archimedes Principle. Retrieved July 4, 2012 from http//www. physicslabs. umb. edu/Physics/sum07/181_Exp9_Sum07. 3. Johnston, J. (2011). Density Definition. Retrieved July 7, 2012 from http//www. densitydefinition. com/ 4. Bell, E. T. (1937). The mathematical achievements and methodologies of Archimedes Electronic version. Men of mathematics. Retrieved July 8, 2012 from http//mathdb. org/articles/archimedes/e_archimedes. htmBk03 5. Skyline College, chemistry 210 Laboratory Manual (2010).Determination of the density of water and unknown solid sample. Retrieved July 7, 2012 from http//www. smccd. edu/accounts/batesa/chem210/lab/labmanual/Density2010. pdf 6. Walker, R. (1998). Density of Materials. Retrieved July 8, 2012 from http//www. simetric. co. uk/index. htm 7. Brooks P. R. , Curl R. F. , Weisman R. B. (1992). Investigatin g the relationship between the mass of a liquid and its volume Electronic version. Introductory Quantitative. pages 16-19. Retrieved July 8, 2012 from http//www. terrificscience. org/lessonpdfs/MassVolumeofLiquid. pdf