This experiment was performed to observe differences in density based on the chemical makeup of an object. Pennies minted before 1982, pennies minted after 1982, and an unknown metal sample was tested to see if there were any differences in their densities. Ten pennies from each category and the metal sample were weighed using a scale to find mass and the displacement method was used to find their volumes. The masses and volumes were then used to calculate the densities of the pennies (D=m/v). The density of the pre-1982 pennies were 8.6 g/mL while the post-1982 pennies were 6.9 g/mL. The metal sample’s density was 1.7 g/mL. Following the experiment we were given the real densities of each item to calculate the percent error with the formula
There are several sources of error to this experiment due to random and systematic errors. The only source of random error was the measurement that we took through the graduated cylinder which was only accurate to the nearest 1%. We took the largest error from this one percent, which was +/- 3. The largest relative error this yielded was only 3%, so this did not affect how precise this experiment was too much. We can still make this more precise by making the masses of the water larger. For example if we started the masses at 300mL and went up by 50mL, the largest error this would yield would be 2% due to the largest error being +/- 5. This would cause smaller errors in the amount of water.
The purpose of this lab was to identify unknown substances using density. We had three unknown substances; a yellow liquid and two metal rods. For each substance we measured volume using the water displacement method in a graduated cylinder and mass using a triple beam balance. Then we calculated density
Calculating the percentage uncertainty for a 250 mL volumetric flask The uncertainty for a 250 mL volumetric flask is ± 0.15 mL. The volume is 250 mL when the flask is full. To calculate percent uncertainty: (0.15 mL)/(250 mL)*100=0.06%
Procedures The purpose of this experiment was to test multiple brands of popcorn under the same setting in order to conclude which one statistically popped the most kernels. I tested the butter flavor of Orville Redenbacher, Wal-mart’s Great Value brand, and Pop Weavers. The different bags of popcorn were popped in the same microwave for the same amount of time, 3 minutes and 15 seconds. Then, the popped corn was counted, as well as the un-popped kernels, in order to determine a ratio, and then I recorded the results in the data table. I repeated these steps two more times for a total of 3 trails for each brand. Then I compared the ratios of all the bags to determine which brand yielded the most popped corn. The statistical technique used to evaluate the data was to find a ratio between the number of kernels in the bottom of the bowl and the number of popped kernels. To find this, I divided the number of the actual popped corns by the total number of kernels left in the bottom of the bowl. The ratios and percent were then compared. Once all my results were in the data table, I averaged the 3 trials for each brand of popcorn.
9. The accepted value for the density of water is 1 g/mL and the accepted density for isopropyl alcohol is 0.786 g/mL. Determine the percent error between your calculated densities and the accepted values for both water and isopropyl alcohol. Record the percent error in Data Table 4.
Determining the volume of the zinc and copper mixtures each, and record the data. Using equation get the density of the pennies. Compare the results. Find the best-fit straight line. Material: Then calculate the error%=0.01%, and the deviation%=9.74%. Weight 30 dry pre-82 pennies which get 89.77g, using 30ml initial volume measuring the volume of 30 pennies, record the data 10.0ml. Using equation Density= Mass/Volume, get the density of the pre-82 pennies is 8.98g/ml. Then calculate the error%=0.10%, and the deviation%=1.29%.
The purpose of this experiment was to mix Alka-Seltzer with Hydrochloric acid in order to analyze Sodium Bicarbonate as an active ingredient in the Alka-Seltzer. The mixture will contain hydrochloric acid to only see the composition of Sodium Bicarbonate in the tablet once it reacts. The amount that reacted allowed
The volume and the boiling point of each collected sample was recorded in a table (for Fractions A, B, and C). The data in the table was converted into a graph (both of which are attached to the back of the report). There is, like in all experiments, an ideal set of data. In this experiment, if the distillation for the unknown mixture (which has two compounds) was done properly, the temperature vs. volume graph should show two plateaus for temperature. (See hand drawn graph attached on back). We look at the plateau temperatures because they are essential to find out what the unknown compounds are. This is because the plateau temperatures show us the boiling point ranges for the unknown compounds. In addition, as shown in the table and calculations attached to back, the volume of the collected sample can be utilized to figure out a ratio of the compounds. But, of course, since ideal and pure samples were not collected, the ratios that are calculated are just estimates. There is one plateau for the boiling point of both lower and higher boiling point compounds. The lower boiling point plateau comes first. The transition phase that occurs between the first and second plateaus was collected. This transition phase represented the mixture of the two compounds in the experiment. If the experiment yielded ideal results, sample A would show to be consisted of primarily the lower boiling point compound. This would be the case up to the point when the temperature is raised to match the boiling point of the higher boiling point compound. The compound is sample C. During the experiment this sample was gathered in a falcon tube. But there is some error in my results. Some of the reasons why there was error in the experiment are stated. I boiled Fraction A for too long, the boiling rate was too high, or a combination of these errors occurred. If the boiling rate is too fast, the side arm will heat up as the
Abstract In Measuring and Understanding Density, several experiments were performed to find density of regularly shaped objects, irregularly shaped objects, liquids and gasses. An additional experiment was done to find the specific gravity of a sampling of liquids. The purpose of the experiment was to provide a better understanding of density and to be able to extrapolate unknowns based upon these calculations. The experiments yielded data in keeping with Kinetic-molecular theory in regards to the density of water versus its temperature. Key measurements and formulae were also used to determine densities of metal and plastic objects as well as irregularly shaped rocks. It is possible to find the density of an object (be it liquid, gas or
All of the tests were fair enough. Our first experiment was ⅓ (667 milliliters) and that test went very well. Our second experiment was ½ (1000 milliliters),⅓ (667 milliliters), and ¼ (500 milliliters). We tested all three bottle and it came down to two water amounts which were ½ (1000
The purpose of this experiment is to determine the molar mass of an unknown volatile organic liquid, using methods such as, the Dumas method, and then state its identity. Introduction In this experiment, we will collect data from the sample and use the Ideal Gas Law: PV = nRT to portray its pressure/volume/temperature behaviours.
2) Is one region significantly more diverse than the other two? Support your answer using statistics, as we have done earlier in the course. After performing three t-tests, one for Lawn 1 v. Lawn 2, a second for Lawn 1 v. Edge, and a third for Lawn 2 v. Edge, there
Determining Mass and DensityPart A: Mass of nickel Weighing boat, nickel, a pair of forceps and chem-wipe paper were used tocarry out the experiment. Our equipment for this experiment was moved to an electronic balance inthe lab. Once the nickel was cleaned with a chem-wipe paper, it was transported intothe
The aim of this experiment was to test the heat of combustion over a period of time, and the energy required to combust alcohols with different carbon chain levels. It was hypothesised that the higher the carbon chain of the alcohol present, the faster the heat of combustion will occur.