Sources of Error in Our Implementation
Systematic errors
> The temperatures on the mercury thermometer may be inexact e.g. may
be out by one degree centigrade.
> It has been assumed the volume of gas is contained in a compete
cylinder when in fact this is not necessarily true, due to:
o Spherical shape of the sulphuric bead above it
o Residue in the tube
o Changes of diameter within cylinder
> The volume of air is being partly compresses by the weight of the
sulphuric acid bead above it. Therefore the volume may not
increase/decrease in proportion to how it would do naturally
Random Errors
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> Eye reading of temperature readings are likely to cause a certain
amount of inaccuracies.
> The curve of the liquid bubble could lead to readings taken from
different parts of the bubble making the results inaccurate.
Most Significant Error
The most significant systematic error is the measuring of the
temperature of gas inside the capillary bubble. Because it is not
realistically possible to measure the gas bubble directly ,the water
bath surrounding it is measured on the assumption that they are both
the same temperature. This may be inaccurate because:
- Air inside the capillary of the bubble has a different specific heat
capacity than the water in the beaker; therefore even with the same
amount of energy applied to both substances they will emit different
amounts of heat
- Air bubble is insulated by the glass capillary, therefore it is
likely the gas bubble may be at a lower temperature than the
thermometers suggests
Error estimation
The Reading of the height of the bubble c...
... middle of paper ...
...his is because the
equipment used is not complex and there are few things to go wrong.
This reduces the likeliness of their being anomalous results.
Looking at the table, there is an anomaly of results between the 90
and 100 degree readings of the second repetition. Despite a rise of
ten degrees centigrade, there is difference in the height of the
bubble when heated between. This is surprising because in all the
other results as more heat is added the height of the bubble
increases.
This can be explained by the nature of liquid mercury in the
thermometer. Like all liquids it is cohesive making it stick to the
sides of surfaces. Therefore the mercury may not expand smoothly, but
in spurts where the expanding force exceeds the cohesive force of
sticking to the sides resulting in false measurements of temperature.
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
However, the increased temperature of the new acid solution was at a greater temperature than the ambient temperature and the temperature of the water. This suggests that some of the results obtained were partially due to the fact that some of the heat energy of the acid was transferred to the water, as well as the hydration of ions present in solution. An improvement would be to create the solutions of desired concentration and allow them to reach thermal equilibrium with the surroundings. This would allow more accurate results and the allow for the assumption that the temperature change observed during the experiment would only be due to hydration of
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...
Evaluation I think that the method used in the experiment is not very accurate because the way we measure the amount of gas produced is not very
The molar volume of the H2 in our experiment is very close to the theoretical molar volume, but I think that the deviation lies in the temperature of the H2O: in the first trial it is too high and in the second one too low.
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.
Variables --------- During the experiments, the water will be heated using different spirit burners containing different alcohols. I will be able to change different parts of the experiment. These are the. Volume of water heated:
Experimental Summary: First, my partner and I put the marshmallow and cheese puff on T-pins and used the Electronic Balance to measure the mass of each of them. Next, we put 100 mL of water in the 100 mL Graduated Cylinder and poured it into the 12 oz. soda can. We measured the temperature of the water with the thermometer. After
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.
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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.