Chem Lab Report

Names: Asa Noteboom, Michael Mcintosh, Chibu Enemuo GE: Preeti bhattacharjee - 21059 1/31/23 Lab Report Materials and Method In the first experiment there were two methods used for finding the densities of different sized blocks. The first method used was the caliper method. This method required us to find the mass and dimensions of the block with the caliper measuring tool, then finding the density. WE repeated this process with all four blocks. The second method we used was the water displacement method. This method required us to put the block in water and acquire the density of the block using the change in volume of water. We repeated this process with all four blocks. The tools used to conduct this experiment were beakers, the caliper tool, the analytical balance, and 4 different sizes of copper. In the second experiment we acquired 2 different types of the same brand of soda, Diet Coke, and regular Coke. First, we poured the different types of cokes into separate beakers, then labeled the beakers. Afterwards we would weigh two empty beakers, one for the diet coke and one for the regular coke. Then we poured different amounts of diet/regular coke in its labeled beaker (6ml/11ml/). Next we got the new weight of the diet/regular coke and recorded it. We repeated this 2 more times with the same amount of diet/regular coke. Safety and Waste Disposal Plan In the first experiment there was no waste except for the water that was used in order to measure the volume of the copper blocks so we were able to just pour that down the sink. In the second experiment we were required to add NaHCO3, better known as baking soda to the coke in order to neutralize the acidity of the coke. After adding a scoop of baking soda to the soda we tested its pH levels in order to determine if it was safe to dispose of down the sink (5.0-12.0). This is required since when a larger quantity of soda is disposed directly down the sink its acidity is strong enough to be considered unsafe to directly dispose down the drain and into the pipes. Gloves were not needed in this experiment, just safety goggles and proper clothing. Data, Observations, Calculations, and Equations Copper: ● Reddish brown tint ● Rectangular ● Cylinder ● Solid ● Heavy for size ● Very smooth Coca-cola & Diet Coke

● Dark brown ● Very carbonated and bubbly ● Fluid ● No differences in appearance between Diet and Regular Coke Part 1 Method 1: Density of Metal using Caliper Method Sample Mass (g) Volume (cm^3) Density (g/cm^3) Avg. Density (g/cm^3) (class) Rectangle (Large) 72.59 8.3 8.746 8.9125 Rectangle (Small) 45.3924 5.223 8.691 8.8260 Cylinder (Large) 78.5401 8.75 8.976 8.9069 Cylinder (Small) 44.851 5.047 8.886 8.9363 Part 1 Method 2: Density of Metal using Water Displacement Sample Mass (g) Volume (mL) Density (g/mL) Avg. Density (g/mL) (class) Rectangle (Large) 78.5946 7.9 9.949 9.0684 Rectangle (Small) 45.3925 4.9 9.264 9.2489 Cylinder (Large) 78.5406 8.9 8.825 9.0243 Cylinder (small) 44.851 5.1 8.794 8.9432 Part 2: Diet Coke vs Regular Coke Sample (Trial #) Mass (g) Volume (mL) Density (g/mL) Average density for Diet and regular Coke (g/mL) Diet Coke 1 11.0744 11mL 1.0069 .9931

Avg D = (1.029 g/mL + 1.029 g/mL + 1.028 g/mL)/3 Avg D= 1.0287 g/mL Claims Which of the two methods for calculating the density of Cu blocks is more accurate (water displacement or calipers method)? The method that was more accurate for calculating the density of the Cu blocks was the Caliper method. According to the first table, the average density from the blocks using the caliper method have less standard deviation than the average density of the blocks using the water displacement method. Does the size/shape of the Cu blocks affect the density? No, the size/shape of the Cu blocks does not have an affect on the density. Looking at our tables the average densities of the blocks using the caliper method all fall in the 8g/ml3 while the densities of the blocks using the water displacement method were all in the 8-9g/mL3. Which is more dense, regular soda or diet soda, and why? (Do the differences in ingredients between regular coke vs. diet coke affect the densities of the two?) Regular soda is more dense than diet soda because one ingredient that regular soda has that diet doesn’t is sugar. Diet soda uses sweetener instead of sugar, causing it to have a slightly lower density than regular soda. Evidence and Analysis The method we determined to be the most accurate in determining the density of the copper blocks was the caliper method in comparison to the water displacement method which was not the same as the class averages seeing as the class average for caliper was 8.895g/cm^3 and the average for the water displacement was 9.012g/cm^3 in general. I believe this was due to a skew in the data which is causing the average to be lower in the caliper than it should actually be when the skew is removed the average for the caliper method is 8.918 g/cm^3 which is closer to the predicted value of copper showing that the caliper method is a more accurate measuring tool for determining the density of copper. This makes sense since for the caliper method we recorded measurements into the hundredth place when for the water displacement method we only measured into the ten’s place. The calipers errors are considered indeterminate and the water displacement errors would be determinate as well. The size and shape doesn’t affect the density of the copper seeing as the large and small rectangles both produced densities of 8.691g/cm^3 and 8.746 g/cm^3 according to our data which is very similar to that of the class, also the shape doesn’t have an effect since the density of the cylinder was averaged to be 8.810g/cm^3 which is also very similar to that of the rectangles. This density will remain constant throughout any shape or sized piece of copper since the ratio between mass and volume of an element is constant meaning nothing physical would affect its density. The regular coke had a density of 1.0287 g/mL and the diet coke had a density of Avg D = .99731 g/mL. This shows how regular coke has a greater density than diet coke proving it’s more dense. This can be

attributed to the fact that diet coke has sweeteners such as Aspartame which is different from regular coke which just uses high fructose corn syrup. The sweetener that is added to the diet coke is not as dense as that added to the regular coke which is observed in the ingredient label with diet coke having less than 1g of total carbohydrates and regular coke having 55g. This would explain why the diet coke is less dense than the regular coke since density is D=m/V and since the regular coke has more carbohydrates in it it would cause it to be slightly heavier making the density slightly more than the diet coke. Reading and Reflection Errors that could have affected our results in this experiment are filling up the pipet and the graduated cylinder inaccurately. These errors would be determinate and would cause inaccurate measurements of the densities in both the water displacement method, and the soda experiment. An example of indeterminate errors would be if the pipette was somehow malfunctioning and not properly dispersing all of the liquid even accounting for the plus/minus. Self and Lab Partner Evaluation for Group Report We worked very well as a group and all contributed equally to this project. We all collected the data we were supposed to in class with not one person taking a commanding role and doing all the work by themselves and also no one let other people pick up their slack. We were mistaken on which parts of the assignment were meant to be submitted causing slight miscommunications on the Lab Report but we all worked together in order to get it complete before the due date. Overall a very cohesive group which needed no adjusting.