1. Your percent recoveries for salt and sand should each be approximately 100%. If either (or both) of your salt and sand percent recoveries is greater than 105% or less than 95%, discuss any experimental errors or observations you made that could explain your results.

2. Error Analysis: A student's recoveries of salt and sand were: Salt: 120% Sand: 80%. Describe one experimental error (not a weighing or data recording error) that could explain both the high salt recovery and low sand recovery.

3. How many significant figures should there be in the answer to this calculation?

(56.62 - 55.92) / 55.92 * 100%

what kind of value is being calculated by this expression?

4. Which procedure (the sand recovery procedure or the salt recovery procedure) do you think would consistently give the most accurate results based on your experience today? Explain your answer.

Lab 1: Investigating Density Discussion Questions: 1. Record the alcohol density determined by another pair of students: Other students' names Density value(s). a. Are their density values close to yours (within +/-0.05 g/mL)? b. Theoretically, should the densities be approximately the same value? Why or why not? 2. Do significant figures matter? Students A and B recorded these measurements at the same time for the same alcohol sample using the same equipment you used. The only differences were how they read and recorded each measurement Student B Measurement Mass of empty 10 ml cylinder Mass of cylinder and alcohol Volume of alcohol Calculated density % error (True value for sample=0.830 g/mL) Student A 23.303 g 30.395 g 8.61ml 23.3 g 30.38 9.0 mL Calculate the density and percent error for each set of data and write these values in the table. a. Which student's percent error is greater? b. What types of errors in reading measurements and recording data were made by the student with the greater percent error? 3. Error analysis: While performing Part B, some of the water splashed out when the sulfur chunks were added to the graduated cylinder. Think about each step in Part B and review the calculations, then explain whether this error will make the calculated sulfur density value too high, too low, or have no effect on the calculated value