experiment 2_ density exploration lab report (2)

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Feb 20, 2024

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Alexia Calderon Martinez Abby B, Abby R, Grace F Paul Abi - 21191 02/06/2024 Experiment Two: Density Exploration Materials and Methods: write a brief procedure (no more than 1 paragraph per experiment) for parts A and B. Specify what materials and equipment you are using in the lab for parts A and B. Procedure: Part A: Begin with discussing with your group which method and copper piece you are going to use. After that it is decided to record which method you will be proceeding with and record observations of your copper piece. Once you have recorded observations, put water into a beaker, using a pipette of 10 mL, get 10 mL of water from the beaker and put it into the graduated cylinder. Once you have done that, put the copper piece into the graduated cylinder, take note of the final volume with the copper piece in the graduated cylinder. After that is taken down, take the mass of the graduated cylinder, with the water and copper piece still in it. After that is done, subtract the final volume by the initial volume to get your volume, then do the mass divided by the volume to get your density. Write down ALL data, after your data is in your notebook or on the data collection, switch copper pieces with your lab partner and repeat these steps. Part B: Begin with deciding which soft drink you are going to use, either sweetened or unsweetened and get said volume from the lab instructor. Record which one you will be measuring and the volume you will be using. Obtain some of the soft drink into the 100 mL beaker. First practice using the volumetric pipet using water, after practicing rinse the pipet twice using the soft drink. Find the mass of an empty 50 mL beaker. Using the volumetric pipet to obtain your said volume from the 100 mL beaker and put that into the 50 mL beaker, after putting said volume into the beaker take the mass of the 50 mL beaker WITH the soft drink. Record your data, after recording your data, subtract the mass of the 50 mL beaker with the soft drink by the mass of an empty 50 mL beaker, then divide that by the volume you received from your lab instructor. Repeat again 3 times.

Materials: Part A Part B Copper piece Graduated cylinder Water Beaker Pipette Scale 100 mL beaker 50 mL beaker volumetric pipet Scale Soft drink (sweetened or unsweetened) Safety and Dispose Plan: summarize how you handled the waste generated in this experiment. Copper: Take copper out of the graduated cylinder by going to the sink and carefully tilting the graduated cylinder where the water is spilling out and your hand is ready to catch the copper piece once it is out. Soft Drinks: Pour your soft drink into the biggest beaker on your lab table. Take that to the center of the lab room and put in around a scoop of the neutralizer, mix that in using the mixer at your station, when it is all mixed together, using the mixer put a drop of your now neutralizer + soft drink on the ph level paper, if it turns green or if its ph level is over a 6 it is now neutralized and can be poured down the sink. Data, Observations, Calculations, and Equations: enter your data and observations here - Observations of metals-physical appearance Rectangular - Large Rectangular - Small Cylinder - Large Cylinder - Small - Taller - Copper with some rust - No smell - smooth - Solid - Rectangular prism - Solid - No smell - Smooth - Short - Copper with some rust - Rectangular prism - Taller - Copper with some rust - No smell - smooth - Solid - Cylinder - Solid - No smell - Smooth - Short - Copper with some rust - Cylinder Diet Coke Regular Coke Lighter shade of brown/more transparent Diet smells very artificial Diet coke is a water-like consistency Darker shade of brown/darker Regular coke smells about the same Regular coke is a little thicker than water

Part 1 Method 1: Density of Metal Using Caliper Method Sample Length (mm) Width (mm) Height (mm) Mass (g) Volume (cm^3) Density (g/cm^3) Average Density (g/cm^3) for the Cu blocks Rectangular - large (Data from: Abby R) 12.69 12.69 50.82 72.5892 8.18385 4602 8.8698 8.8395 Rectangular - small (Data from: Abby R) 12.69 12.69 31.83 45.3793 5.12577 9063 8.8698 8.8376 Diameter (mm) Cylinder - Large (Data from: Abby B) 44.47 15.9 78.476 8.8420 6449 8.8753 8.9440 Cylinder - Small (Data from: Abby B) 25.43 15.91 44.8274 5.0499 46745 8.8768 8.9322 Part 1 Method 2: Density of Metal Using Water Displacement Sample Initial Volume (mL) Final Volume (mL) Mass (g) Volume displacement Density (g/cm^3) Average Density (units) for the Cu blocks Rectangular - Large 10 18 72.3792 8 9.0474 9.1726 Rectangular - Small 10 15 45.3793 5 9.0759 9.6455 Cylinder - Large (Data from: Grace F) 10 19 78.4801 9 8.7200 9.2925 Cylinder - Small (Data from: Grace F) 10 15 44.8274 5 8.9655 9.1707 Part 2: Diet Coke Versus Regular Coke Sample Mass (g) Volume (mL) Density (g/mL) Average Density for Diet and

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Regular Coke Regular Coke - 6 mL (Data from: Abby B) 6.218 6 1.0363 1.02 Regular Coke - 11 mL (Data from: Emery P) 11.819 11 1.0745 Regular Coke - 15 mL (Data from: Sophie P) 15.485 15 1.0323 Diet Coke - 6 mL (Data from: Hawk B) 5.971 6 0.9952 1.00 Diet Coke - 11 mL 11.0691 11 1.0063 Diet Coke - 15 mL (Data from: Owens S) 14.8655 15 0.9910 Data and Observations: include a sample calculation in your notebook for: ● Calculation of density of metals by method A and calculation of average density. ● Calculation of density of metals by method B and calculation of average density. ● Calculation of density of diet coke and calculations of average density. ● Calculation of density of regular coke and calculations of average density. Claim(s): a claim is a statement that answers the class beginning questions. Answer each question in complete sentences. Copper : The same pieces of copper did not have the same densities using both methods. With more confidence I would use the caliper method, as you can get closer to accurate information making it more difficult to have an outside force messing your accuracy up. The density of copper does not change based on size, instead density is consistent throughout. It is appropriate to calculate an average for the density, because we have so many determinations of each sample, it helps find a balance. Soft Drinks : I used the unsweetened drink, the average density that I determined was 0.9484. g/mL. My results ended up being around the same density as students who used the same volume (6 mL) as I. Using different volumes, we received different answers that were about 0.04 g/mL away from each other, the volume being used does not make a difference in the density as density stays consistent. Based on the class’

data, I would say density is intensive. Experimental error when using the pipet can be very likely, as it is easy to go even just a little bit under or over the line already causing a change in your data. This would inﬂuence the data, because he has already reported one piece of data, but it is off which can at times mess up the rest of the experiment. The density of the sweetened soft drink is greater than the density of the unsweetened soft drink, this can be due to the amount of sugar present in said soft drink. Evidence and Analysis: in no more than a paragraph provide support for each claim with evidence. Evidence comes from data and observations. Copper : The same pieces of copper did not have the same exact densities but had very similar densities almost the same. When looking at the data table it can be seen, that each person taking the data got around the same numbers for both their samples, but comparing all the data together; rectangular - large using the caliper method was 8.8395 g/cm^3 and the rectangular - large using the water displacement method was 9.1726 g/cm^3, these two are the same pieces but there is a 0.3331 g/cm^3 difference between the both of them. We can infer that while taking the density of copper using the water displacement can have multiple outside forces that can lead to a mishap when taking the density, this could be putting in too much water for the initial volume, not reading the numbers on the beaker correctly, etc. I believe the caliper method is the better method, because I think less outside factors will be inﬂuencing the density, whereas the water displacement method could have multiple outside factors that could inﬂuence the density. Soft Drinks : When using different volumes I believe that you will get around the same answers but because of outside factors will not all be exactly the same. I believe density is intensive because even though all our final densities are different they are approximately the same, this could be due to outside forces, when taking mass, when measuring the volume, etc. I think experimental error is highly likely as there are many outside factors that can contribute to experimental error, this could be rushing through the experiment, using the pipette incorrectly, not closing the scale walls, etc. if there is an outside factor that misreports one piece of data in the experiment it can lead to multiple other things in your experiment being incorrect. The density of the sweetened soft drink is greater than the density of the unsweetened soft drink, this could be seen in our class average as the sweetened soft drink was 1.02 g/mL and the unsweetened soft drink was 1.00 g/mL.

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