Synopsis This laboratory report gives an outline of the experiment which was carried out in order to measure the density of water at different temperatures via two different methods. The lab consisted of two parts. In the first part the density of water was measured by hydrometer. At first the density of water at room temperature was measured. In the next steps the density of water between 30-40 °C, 40-50 °C and 50-60 °C was measured. Then our results ρ vs T and also density vs temperature values given in the Steam Tables were plotted on the same graph in order to compare. In the second part the density of water was measured by density bottle. The densities obtained from the experiment are 995, 992.5, 991, 990 kg/m3 for the first part and …show more content…
Again we will use ρ=m/V in order to calculate the density of water. Experimental technique The first part of experiment is done in following steps: The second part of experiment is done in following steps: Results The density of water by using hydrometer: 1. 26.5 °C room temperature 2. 37.8 °C and 36.3 °C 30-40 °C 3. 41.7 °C and 40.2 ° C 40-50 °C 4. 50 °C and 48 ° C 50-60 °C Average temperatures: (37.8+36.3)/2=37.05 °C (41.7+40.2)/2=40.95 °C (50+48)/2=49 °C Table 1 -The values of experiment Temperature (°C) Density (kg/m3) 26.5 995 37.05 992.5 40.95 991 49 990 70 984.856 80 982.524 90 980.272 100 977.93 Table 2. The values in steam table Temperature (°C) Density (kg/m3) 26.5 997 37.05 993 40.95 …show more content…
These small errors may be arised as a result of temperature. Because the accurate mesuring process took much time and during this time the temperature of water was decreasing. Among two methods the density bottle gives more accurate measurement of the volume, resulting in more accurate determination of density. One of disadvantages of hydrometer is that hydrometer has Operator dependent readings, therefore has limited accuracy. Morever, for measuring the density using hydrometer large sample volume is required. Conclusion In conclusion, almost our group reached main target. We used two different methods which were hydrometer and density bottle method in order to measure the density of water at different temperatures. We calculated the densities of water which were 995, 992.5, 991, 990 kg/m3 for the first part and 967 kg/m3 for the second part. Finally we compared these two methods in order to decide which method is more suitable. References http://www.middleschoolchemistry.com/lessonplans/chapter3/lesson1 http://chemistry.about.com/od/waterchemistry/f/What-Is-The-Density-Of-Water.htm
By reading the new volume of the liquid substance amount one will then subtract the initial milliliter amount from the final volume reading, thus giving you the volume of the rock sample. Using the mass of the sample rock obtained one will then divide the final volume reading unveiling the density of the
First the ball had a small hole directly in the center and the rod had an uneven end these presented challenges for getting an accurate measurement in step III. Second the errors in the measurements were carried through and expanded by the calculations performed. The obtaining the volume via the displacement method was only one step without calculations. Thus I believe the displacement method produce better measurments. 4.
After the data is collected, a graph of water temperature and amount of blubber will be
Two trials for each liquid will be run. Molar mass, boiling point will be found using outside
3mL of the liquid in each of the vials were added into cuvettes and measured in the spectrophotometer. Before each time point the photo spectrometer was zeroed using a cuvette with 3mL of distilled water. If any of the results were considered unusual the machine was zeroed again and the sample was retested. The results from the spectrophotometer test were recorded in a table. The experiment was repeated six times to gain a sample size of six.
Introduction The intent of this experiment is to understand how hot and cold water interact with each other by combining clear hot water and black ice cold water. I hope to learn more about how hot and cold water interact with each other. As of now, I know that cold water is denser than hot water. Knowing this I formed my hypothesis.
This was especially important in the measurement of liquids, with +/- 0.05 millilitre differences in either the Hydrogen or the distilled water. Since these two liquids get added together, the error values add to create an overall uncertainty sum. This therefore provides the ASS and solution combined an error uncertainty of +/- 0.1mL. Due to the nature of this experiment however, this error is neglect able and the general trends form with high
Research Question: To investigate and compare how different temperature (5℃, 15℃, 25℃, 35℃, 45℃) can affect the concentration of carbon dioxide in soda water through titration with sodium hydroxide solution. Introduction: Carbon dioxide plays an important role in soft drinks. Soda water is manufactured by pumping carbon dioxide into water under high pressure. Carbon dioxide dissolves in water to form carbonic acid, which is the fizz we find in soft drinks. CO2 + H2O ⇌
The observed emission data for the different elements did not look how they were supposed to. However the “peaks” for Hydrogen were found to be 534.52 and 631.24, 534.70 and 569.11 for Helium and 529.73 and 630.71 for Mercury. The Rydberg’s Constant found to 1.1x107 8.5x104 while the known constant is 10967758.34m-1. The percent error of 0.29% and the accuracy of this reading is 99.7. The slope and intercept of the linear regression line is -0.01 3.3x10-5 and 0.02x10-1 1.9x10-6 respectfully.
We also looked at outliers (results that are odd and to not math with other trial of same concentration), that may have occurred due to errors such as reaction error or random error etc. We fixed these trials but repeating those trials again and neglecting the outlier. To make sure the investigation was as accurate as possible; we kept results that were between 0.1cm difference. Another way we made sure the experiment was fairly tested and valid was by prevented parallax error. We prevented this by making sure to read scales accurately, such as when measuring the volume in the measuring cylinder and measuring the height of foam/ gas produced by the breaking down of h2o2 using
Research question What is the effect of temperature Amylase activity? Word count-1453 Background research Enzymes are biological catalysts that speed up a chemical reactions. They do this by decreasing the activation energy(the energy needed to start the reaction) of a chemical reaction. The enzyme present in our saliva is called Amylase. Amylase increases the rate of reaction by decreasing the activation energy needed to hydrolyse the starch molecules.
In this experiment, the amount of water lost in the 0.99 gram sample of hydrated salt was 0.35 grams, meaning that 35.4% of the salt’s mass was water. The unknown salt’s percent water is closest to that of Copper (II) Sulfate Pentahydrate, or CuSO4 ⋅ 5H2O. The percent error from the accepted percent water in CuSO4 ⋅ 5H2O is 1.67%, since the calculated value came out to be 0.6 less than the accepted value of 36.0%.This lab may have had some issues or sources of error, including the possibility of insufficient heating, meaning that some water may not have evaporated, that the scale was uncalibrated, or that the evaporating dish was still hot while being measured. This would have resulted in convection currents pushing up on the plate and making it seem lighter by lifting it up
Moreover, it can be seen that the cooling capacity could gain 685.4 W when Tg = 65 °C and 482.8 W when Tg = 55 °C. With the increase in generating temperature, the cooling capacity decreased at first and then increased when the generating temperatures ranged from 40 °C to 70 °C. The experiment was repeated under the same conditions. Figure 4 illustrates the effect of the generating temperature on the system COP, cooling capacity and critical condensing temperature of the steam ejector when the generating temperatures ranged from 60 °C to 70 °C.
Introduction Buffer is a solution that resists a change in pH when bases or acid are added. Solutions that are acidic contain high concentrations of hydrogen ions (H+) and have pH values less than seven. Buffer usually consist of a weak acid, and its conjugate base or a weak base and its conjugate acid. The function of buffer is to resist the changes in hydrogen ion concentration as a result of internal and environmental factor. This buffer experiment is important so that we relies the important of buffer in our life.
Synopsis This experiment is the determination of Calcium Carbonate (CaCO3) content in toothpaste with the use of back titration while demonstrating quantitative transfer of solids and liquids. A accurately weighed quantity of toothpaste was dissolved in excess volumes of HCl. This solution is then titrated with NaOH to find the volume of the excess HCl. The volume of HCl reacted, which is found by substracting the volume of given HCl with the volume of excess HCl reacted, can be further manipulated with mole fractions to find the mass of CaCO3 and thus the CaCO3 content in toothpastes.