Calorimetry Lab Report

Michelle Pham mtp738 50575 Experiment 1 Measurement and Density The objective of the experiment is to understand measurement and density by comparing the density of Diet Coke and Coke. The experiment is also meant to help further the understanding and use of lab equipment as well as the basic foundation to starting and analyzing lab data. Random error is an unpredictable error that slightly affects the precision of data.

2. In order to calculate the density of a solid or liquid sample, what measurements are needed?

There are only 25 numbers in the sample collected. For purposes of analysis, it will be considered that the process itself is normally distributed, and its standard deviation is unknown. Under these conditions, the formula that gives the confidence interval is:

The pennies that were dropped into the graduated cylinder could have caused some of the water to splash out of it. This may have caused an error in measuring the volume, this would have caused the volume measured to be less than the actual volume, thus allowing the density of the pennies to increase, causing the lab results to be uneven. Another source of error has to do with the mass of the pennies. After the pennies were taken out of the graduated cylinders filled with water, there was still some water droplets left on the pennies when put on the triple beam balance. This extra weight of the water may have caused the measurement in the mass of the pennies to be more than they actually were. This outcome could have caused the density of the pennies to be increased as well, making the lab results inconstant. Any type of coating, for example rust, on the penny may affect the mass. This will add to the mass making it higher, and since density is proportional to the mass, the density will be calculated higher than what it actually

What is density? Density is the degree of compactness of a substance. The density formula is D=Mass divided by Volume. While doing this experiment you will need a graduated cylinder, electric balance and water displacement method to find the density of pennies after 1982. Water displacement is the volume in measure of the amount of space an object takes up. The differences between pennies before 1982 and after 1982 is after 1982 the government decided to put less copper because copper was way to expensive. Pennies before 1982 contained 95% copper, zinc 5% so then after 1982 they started using 95% zinc, and 5% copper. The objective of the lab was to find the density of a penny after 1982 to compare how big the difference was from before 1982

Nothing Experiment 8 0.173 0.002 0.026 0.128 Experiment 9 0.226 0 0.047 0.162 Part B

Slope determination is a valid way to calculate density because the slope of the data and the actual slope were close in value. When looking at the slope of the graph with the points, they were all relatively close. Three of the five point were even on the slope line. The formula of (y2-y1/x2-x1) allowed the finding of the slope of the line graphed and it also allowed the comparison to the actual slope of silver. This allowed the calculation of the percent error and also to see how effective slope determination really is. The slope of silver was 10.5g/cm³ and the slope of my findings was 10.15g/cm³. The percent error was low at 3.3% which points to slope determination

18) A sample of candies have weights that vary from 2.35 grams to 4.75 grams. Use this information to find the upper and lower limits of the first class if you wish to construct a frequency distribution with 12 classes. A) 2.35-2.65 Answer: B 19) Assume that the heights of men are normally distributed. A random sample of 16 men have a mean height of 67.5 inches and a standard deviation of 1.4 inches. Construct a 99% confidence interval for the population standard deviation, . A) (0.8, 2.1) B) (1.0, 2.6) C) (0.9, 2.5) D) (1.0, 2.4) Answer: C B) 2.35-2.55 C) 2.35-2.54 D) 2.35-2.75

The measured density of the bulk beads in the second data set is 2.63g/cm3. The uncertainty of the density measurement is 0.02g/cm3 and the percent uncertainty is 0.83%. Again, the average density from the individual bead measurements in this data set is 2.57g and the percent of uncertainty is 0.36%. The percent of uncertainty is higher with the bulk beads; however, the measured densities are similar. The measured difference between the bulk and individual beads is 0.06g/cm3. The measured tolerance of the density between the bulk and individual beads is 0.077g/cm3. The measured difference between the beads is less than the measured tolerance, therefore, the two density values agree.

We want to calculate the mean for the 10 rolls of the die for each student in the class. Label the column next to die10 in the Worksheet with the word mean. Pull up Calc > Row Statistics and select the radio-button corresponding to Mean. For Input variables: enter all 10 rows of the die data. Go to the Store result in: and select the mean column. Click OK and the mean for each observation will show up in the Worksheet.

Problem 5: (3.5 points). A manufacturing process produces items whose weights are normally distributed, with a mean of 120 grams and standard deviation 10 grams.

The substance with the highest deviation is both metal B and metal D, both with a deviation of 1. The substance with the lowest deviation is solution C. (Data tables of Deviation shown above) The deviations show the precision of my density calculations.

After my experiment I take the mass and volume from the small pieces of clay from all three trials and I find the average which is 14.7g (mass) and 8.7cm3 (volume). Then I divide using thee formula d=m/v and for density I got 1.7g/cm3, rounded to the nearest tenth. Next I did the same for medium of all three trials in which I got 22.5g for the average of the mass and 13.3cm3 for the volume. I divide using the same formula and also got 1.7g/cm3, rounded to the nearest tenth. Lastly I find the average of mass and volume for large of all 3 trials and got 40.1g (mass) and 24.0cm3 (volume). I divide 40.1g and 13.3cm3 and got 1.7g/cm3 for the density, rounded to the nearest tenth. I compare the mass and the difference was 0 (when all are rounded to the nearest tenth) which shows size doesn't really affect density.

Q. Certify less than 5% have errors. 10m per entry. How long to est. % of entries having errors using random sample big enough to get MOE less than 2%.

mag, m = 18.51 ± 0.36, and m = 18.96 ± 0.36, respectively, while their uncertainties