Name: Period: DUE Friday 9/ 16 Honors Chemistry Lab #1: Metric System Introduction: The Metric System is a worldwide standard system of measurement. Scientists must be able to communicate with each other and the public. Before the Metric System there were many non-standard measurements which varied from place to place and country to country. The Metric System is based on units of 10. There are basic units which are in common usage. We are going to look at those today. They are the meter for length, liter for volume, and gram for mass. There are prefixes which we can attach to each unit. Please be familiar with these prefixes and how to convert between them. Table 1. Basic Metric Prefixes Prefix Symbol Number of basic units Exponential Form and comparison kilo k 1000 10 3 1000x bigger hecto h 100 10 2 100x bigger deka (or deca) da 10 10 1 10x bigger Basic Unit gram g 1 10 0 1 liter L 1 meter m 1 deci d 0.1 10-1 1 10 centi c 0.01 milli m 0.001 1 10-2 100 1 10-3 1000 Purpose: The purpose of this lab is to practice using metric units in measurements with the metric ruler, graduated cylinder, and balance. In addition, to employ this equipment in calculating volume, mass and density. Reference Information:
Materials: 1. 150 ml beaker 2. Distilled water 3. Penny 4. Pen 5. Paper 6. Metric ruler 7. Weigh boat 8. 10 ml & 100 ml graduated cylinders 9. thirteen spot reaction well plate. 10. Table top 11. Triple /Quadruple beam balance Procedure 1. Determine the volume of the plastic vial, and table top. in cm 3. Record the measurements for the length, width, and height in data table 1. 2. Find the mass of one penny, a pen, and a piece of paper (8 ½ x 11 size) on the triple beam balance as well as the digital scale. Record in data table 2. 3. Calculate the density of distilled water (record in data table 3) Method 1: a. Mass an empty 150 ml beaker (be sure to write down the uncertain digit in the measurement!) b. Place 100 ml of distilled water in the beaker and re-mass c. Determine the mass of the water (subtract the empty beaker s mass from the filled beaker s mass) d. Determine the density of the water. density = mass/volume (g/ml) 4. Calculate the density of distilled water (record in data table 4) Method 2: a. Mass an empty 100 ml graduated cylinder (be sure to write down the uncertain digit in the measurement!) b. Place 100 ml of distilled water in the graduated cylinder and re-mass c. Determine the mass of the water (subtract the empty graduated cylinder mass from the filled graduated cylinder s mass) d. Determine the density of the water. density = mass/volume (g/ml) 5. Calculate the density of distilled water using an alternate method that you and your group created. (record in data table 5) Method 3: Write the procedure for your method below: a. b. c. d.
Data Tables: (Discuss with your lab partners what needs to be in these data tables before creating the data tables. In the following space proved, construct 5 data tables using a straight edge and label each with a proper title. Be sure to record all measurements to the proper number of digits! Always write down the certain digits + one uncertain (estimated) digit.
Post Lab Questions: 1. Calculate experimental error for calculating the density of water:the actual value for the density of the water is 1.00 g/cm 3 or 1.00 g/ml. (Answer by showing work below.) Actual _ Value Experimental _ Value Experimental _ Error x 100% Actual _ value a. Calculate the experimental error for method #1 b. Calculate the experimental error for method #2 c. Calculate the experimental error for method #2 d. Identify which density of water method was most accurate and explain why you think that this method was more accurate based upon the data that you collected.
2. Explain 3 challenges that your group had while completing this lab activity. 3. What are two possible ways to improve this activity? Explain why you believe that your suggestions will help. 4. Convert 4 g into mg 8. Convert 19 ml into L 5. Convert 782 m into km 9. Convert 6702 cm into m 6. Convert 12400 ml into L 10. Convert 582000 mg into kg
11: Explain how you could calculate the actual volume for the top portion of the thirteen spot reaction well plate. Conclusion: