Lab Report Coefficient of Linear Expansion of a Metal
Introduction
Most solid materials expand upon heating and contract when cooled because it undergoes a change in the energy state of its molecules or atoms. According to the atomic perspective, the average vibrational amplitude of an atom increases as the temperature rises. Each material has a property called ¡§coefficient of linear expansion¡¨ that is indicative of the extent to which a material expands upon heating or contracts when cooling. The coefficient of expansion is re very important to all structures and foundation of buildings to avoid the possibility of collapsing.
Objective
The objective of this experiment is to calculate the coefficient of linear expansion of a metal. The change in length of several materials such as glass, brass, copper, stainless steel and aluminum will be determined and the corresponding coefficient of linear expansion would be calculated.
GROUP #5
Metal
(pyrex)Glass Brass Copper Steel Aluminum
Data T1=27¢XC
T2=95¢XC
L1=0.6m T1=27¢XC
T2=98¢XC
L1=0.6m T1=27¢XC
T2=98¢XC
L1=0.6m T1=27¢XC
T2=98¢XC
L1=0.6m T1=27¢XC
T2=98¢XC
L1=0.6m
t(s) ƒ´L(0.01mm) T (¢XC) ƒ´L(0.01mm) T (¢XC) ƒ´L(0.01mm) T (¢XC) ƒ´L(0.01mm) T(¢XC) ƒ´L(0.01mm) T (¢XC)
10 5 27 10 27 5 27 30 40 19 27
20 9 30 20 30 15 27 40 49 33 27
30 11 45 30 35 28 27 52 68 53 30
40 14 59 45 58 41 38 64 80 71 55
50 15 63 55 77 53 62 71 85 90 72
60 15 69 68 83 66 78 73 88 104 81
70 15 78 83 88 76 84 74 90 106 86
80 15 81 86 90 79 88 74 91 107 88
90 16 83 87 91 79 90 74 92 107 90
100 16 84 87 93 79 91 74 93 108 91
110 16 86 87 93 79 92 74 94 108 93
120 16 88 87 93 79 93 74
95 108 93
130 16 89 87 93 79 94 74 95 109 94
140 16 90 87 93 79 94 74 95 109...
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...llow metal tube was not well insulated, some steam and hot water were leaking out from both sides of the rubber jacket and also though the opening for the thermometer. The results of the data were slightly affected due to heat lost.
After the first specimen rod was done, the percent deviation of glass, copper, stainless steel and aluminum have increased noticeably. One of the reasons is that the metal tube was not able to return back to its original temperature or its normal state within a short period of time, even though it was cooled down by running under the water. Another factor was that the thermometer also could not return to the room temperature.
Conclusion
The experiment was luckily conclused fairly similar to the accepted value. However, because only appoximation of datas and other source of errors, the accuracy of the data could be questionable.
First, 100 mL of regular deionized water was measured using a 100 mL graduated cylinder. This water was then poured into the styrofoam cup that will be used to gather the hot water later. The water level was then marked using a pen on the inside of the cup. The water was then dumped out, and the cup was dried. Next, 100 mL of regular deionized water was measured using a 100 mL graduated cylinder, and the fish tank thermometer was placed in the water. Once the temperature was stabilizing in the graduated cylinder, the marked styrofoam cup was filled to the mark with hot water. Quickly, the temperature of the regular water was recorded immediately before it was poured into the styrofoam cup. The regular/hot water was mixed for a couple seconds, and the fish tank thermometer was then submerged into the water. After approximately 30 seconds, the temperature of the mixture leveled out, and was recorded. This was repeated three
There were no significant error factors that may have affected the arrangement of the lab experiment. Everything went smoothly with relative ease.
The procedure of the lab on day one was to get a ring stand and clamp, then put the substance in the test tube. Then put the test tube in the clamp and then get a Bunsen burner. After that put the Bunsen burner underneath the test tube to heat it. The procedure of the lab for day two was almost exactly the same, except the substances that were used were different. The
The results of this experiment are shown in the compiled student data in Table 1 below.
We must first begin the today’s lab by connecting the thermometer that digitally detects surrounding temperature to the Lab Pro Interface located on the computer via...
Going into details of the article, I realized that the necessary information needed to evaluate the experimental procedures were not included. However, when conducting an experiment, the independent and dependent variable are to be studied before giving a final conclusion.
In this experiment, there were several objectives. First, this lab was designed to determine the difference, if any, between the densities of Coke and Diet Coke. It was designed to evaluate the accuracy and precision of several lab equipment measurements. This lab was also designed to be an introduction to the LabQuest Data and the Logger Pro data analysis database. Random, systematic, and gross errors are errors made during experiments that can have significant effects to the results. Random errors do not really have a specific cause, but still causes a few of the measurements to either be a little high or a little low. Systematic errors occur when there are limitations or mistakes on lab equipment or lab procedures. These kinds of errors cause measurements to be either be always high or always low. The last kind of error is gross errors. Gross errors occur when machines or equipment fail completely. However, gross errors usually occur due to a personal mistake. For this experiment, the number of significant figures is very important and depends on the equipment being used. When using the volumetric pipette and burette, the measurements are rounded to the hundredth place while in a graduated cylinder, it is rounded to the tenth place.
Obtain a sample of metal that has been immersed in boiling water and place it in the cup of water.
Quickly and carefully transfer the heated metal from the test tube to the water in the calorimeter.
The question that was proposed for investigation was: Can the theoretical, actual, and percent yields be determined accurately (Lab Guide pg. 83)?
One possible source of experimental error could be not having a solid measurement of magnesium hydroxide nor citric acid. This is because we were told to measure out between 5.6g-5.8g for magnesium hydroxide and 14g-21g for citric acid. If accuracy measures how closely a measured value is to the accepted value and or true value, then accuracy may not have been an aspect that was achieved in this lab. Therefore, not having a solid precise measurement and accurate measurement was another source of experimental error.
- Temperature was measured after and exact time i.e. 1 minute, 2 minutes, 3 minutes.
There is also the potential of human error within this experiment for example finding the meniscus is important to get an accurate amount using the graduated pipettes and burettes. There is a possibility that at one point in the experiment a chemical was measured inaccurately affecting the results. To resolve this, the experiment should have been repeated three times.
Possible sources of error in this experiment include the inaccuracy of measurements, as correct measurements are vital for the experiment.
Law of elasticity is known as Hooke’s law, showing the relationship between the forces applied to a spring and its elasticity, which states that relationship between small deformation of the object and the displacement or size are directly proportional to loading and the deforming force. According to Hooke’s law, elastic behaviour of solids could explain by the fact that in component ions, molecules, or atoms from normal positions, which is small deformation, are also proportional to the force that causes the displacement. The deforming force might be applied to a solid by squeezing, compressing, stretching twisting, or bending. Accordingly, spring will return to its primary size and shape upon discharge of the load (Tega, 2010).