Lab 1 Report - Gregory Chekerdjian

Answer the table and questions.

Part B - Use the scientific method Read the case study and use your knowledge of the scientific method to identify the observation, hypothesis, experiment, and conclusion. Our English springer spaniels like our neighbors’ children and could play with them all day. We thought our dogs will never dislike any children they will ever meet. Last month when we took our dogs on a trip, we met some German tourists in a park. The dogs loved playing with the foreign family’s children. Our English springer spaniels like all children.   Match the words to the appropriate blanks in the sentences. Make certain each sentence is complete before submitting your answer. View Available Hint(s)for Part B     ResetHelp   returned         "Our English springer spaniels like our neighbors' children" is a(n) observation.target 1 of 4 Allowing the dogs to play with the German family's children is the hypothesis.target 2 of 4 "Our English springer spaniels like all children" is our…

Part B Gather all of your pennies dated before 1982. Then follow the steps to complete the table. Include units as necessary. Record the number of pennies dated before 1982. Weigh (as a group) the pennies dated before 1982. Record the total mass. If you’re unfamiliar with using an electronic balance, watch this video before continuing. Calculate and record the average mass of a single penny. If you need help with the calculation, visit the averaging data section of the math review. number of pennies: 8 combined mass of the pennies (g): 49.2 average mass of a penny (g): 5.525 Part C Now gather all of your pennies dated after 1982. Complete the table for the post-1982 pennies using the same steps from part B. number of pennies: 9 combined mass of the pennies (g): 51.7 average mass of a penny (g): 5.744 Part D In parts B and C, you measured the average mass of each group of pennies. Now you’ll measure their volume. (For this part, assume that the pennies dated before and after…

Part B Gather all of your pennies dated before 1982. Then follow the steps to complete the table. Include units as necessary. Record the number of pennies dated before 1982. Weigh (as a group) the pennies dated before 1982. Record the total mass. If you’re unfamiliar with using an electronic balance, watch this video before continuing. Calculate and record the average mass of a single penny. If you need help with the calculation, visit the averaging data section of the math review. number of pennies: 8 combined mass of the pennies (g): 49.2 average mass of a penny (g): 5.525 Part C Now gather all of your pennies dated after 1982. Complete the table for the post-1982 pennies using the same steps from part B. number of pennies: 9 combined mass of the pennies (g): 51.7 average mass of a penny (g): 5.744 Part D In parts B and C, you measured the average mass of each group of pennies. Now you’ll measure their volume. (For this part, assume that the pennies dated before and after…

Say you glued two samples together; a 5.00 g sample of acrylic with a density of 1.19 g/mL and a 2.35 g sample of Teflon (d = 2.22 g/mL). What is the density of the combined sample? Be careful here and remember the difference between intensive and extensive properties. • View Available Hint(s) 3.252 g/mL Submit Previous Answers

part 1 Which of the following is a best practice in weighing solid samples?   Use weighing paper, a watch glass, a beaker, or some other container to measure mass of your solid samples.   Do not return the mass settings to zero mark; let the next user tare it for you.   Place chemicals directly on the balance pan.   For different trials of an experiment, use multiple balances for your measurements

Which statement is true?   Question 12 options:    Precision is measured by standard deviation.   Precision is measured by error or relative error.   Accuracy is measured by the standard deviation.

How do I solve for the percent value? The sample data calculated the answers but I have no idea how they obtained the percent error values. Calculate sample data #1 with detailed steps.

Part 3: Calculate density of a metal an unknown metal. 1. Using the pictures below, record the displayed data in the data table in the report sheet. Make sure to include the right number of significant figures in the measurements and calculations. Mass measurement 7.1 g Volume of water measurement. There's only one measurement here – the larger image is for magnification only. -20 15 m Volume of water and metal measurement. There's only one measurement here – the larger image is for magnification only. 20 m 15

Which of the following is a best practice in weighing solid samples?   Use weighing paper, a watch glass, a beaker, or some other container to measure mass of your solid samples.   For different trials of an experiment, use multiple balances for your measurements.   Do not return the mass settings to zero mark; let the next user tare it for you.   Place chemicals directly on the balance pan.   Question 10

(number 15, for the second picture)

List which piece of lab equipment would be most useful for each of the following tasks. 1. Hold 50 mL of boiling water. 2. Crush a chunk of chemical into a powder. 3. Heat a beaker of water when a gas line is not available to power any equipment. 4. Measure exactly 42.5 mL of water. 5. Scoop ammonium nitrate out of its container and onto weigh paper to be measured.

Unless otherwise informed, report all answers in standard notation to 3 significant figures.

Laboratory 2 Report Sheet-Lab 2 A.2 Area Your measurements Length = Width = Area = (Show calculations.) Why could two students obtain different values for the calculated areas of the same rectangle? A.3 Volume of a solid by direct measurement Shape of solid Formula for volume of solid 18 Height Width Another student's measurements Volume of the solid (Show calculations of volume including the units.) Length Diameter (if cylinder) Page 3 of 3 482 words 区

Click to see additional instructions An irregular shaped sample of zinc has a mass of 47.3 g. This sample is carefully placed in a graduated cylinder of water with an initial volume of 18.8 mL. The density of zinc is 7.14 g/cm3. What is the final volume of the graduated cylinder containing both water and zinc? mL Mark for Review What's This?

6. Define accuracy. Give the equation used to determine the accuracy of a measurement. 7. Define precision. Give the equation used to determine the precision of a measurement.

List all pictograms that are not hazard symbols but are seen in the laboratory

Question 3

Part C Say you glued two samples together; a 5.00 g sample of acrylic with a density of 1.19 g/mL and a 2.35 g sample of Teflon (d = 2.22 g/mL). What is the density of the combined sample? Be careful here and remember the difference between intensive and extensive properties. • View Available Hint(s) ? 1.29 g/mL

If all the plastics floated in all solutions, what conclusions could you NOT make? a) You can rank all the plastics because the experiment had perfect results. b) You cannot rank the density of these plastics since they all floated in each solution. c) You can rank the density of these plastics since they all floated in each solution. d) All the plastics meet industrial standards.

Why should the selected rule(s) be followed? Weighing wet items will cause the displayed mass to be greater than the actual mass of the object. A residue left on the balance will contaminate the balance pan surface and anything that comes into contact with it afterwards. Objects at any temperature other than room temperature can create air currents which can affect the balance pan, causing the measured mass to be higher or lower than the true mass. There may be discrepancies in accuracy between individual balances.

Question 4

Which of the following is a best practice in weighing solid samples?   Do not return the mass settings to zero mark; let the next user tare it for you.   Use weighing paper, a watch glass, a beaker, or some other container to measure mass of your solid samples.   Place chemicals directly on the balance pan.   For different trials of an experiment, use multiple balances for your measurements.

Please help with #5

A specific answer would help a lot

Fill up the missing data

Which of the following is a best practice in weighing solid samples? A Place chemicals directly on the balance pan. B) Use weighing paper, a watch glass, a beaker, or some other container to measure mass of your solid samples. Do not return the mass settings to zero mark; let the next user tare it for you. For different trials of an experiment, use multiple balances for your measurements.

Make a graph of the average mass vs. year. Make sure axes are labeled. Please please answer super fast please answer as fast as possible

7. Using the tolerance table for volumetric glassware, record the delivered volume and tolerance for a 25 mL volumetric pipette. Use format shown below. 土 士. Count the number of digits. The number of digits equals the number of sig. figs. How many sig. figs. are used to write the volume of a 25 mL volumetric pipette? Write the volume of a 25 mL volumetric flask in liters using the correct sig. figs.