1. LABORATORY GLASSWARE AND EQUIPMENT LAB 2

2. Welcome Welcome to the chemistry lab! Chemistry is a lot of fun, but can be even more so if you are familiar with the equipment you will be using in lab. Remember – whenever there’s glassware or chemicals in use, everyone has to wear goggles!

3. Reading a Meniscus Meniscus and Parallax

4. Types of Glassware Graduated glassware Volumetric (non-graduated) glassware

5. Graduated Glassware Beakers Use: To contain certain volumes of solutions Filtering Flasks Use: To contain certain volumes of solutions Graduated Cylinders Use: To measure out exact volumes. Burets Use: To dispense exact volumes.

6. Volumetric (non-graduated) Glassware Volumetric Pipets Use: To measure out exact volumes. This is the most accurate glassware in lab. Volumetric Flasks Use: To make up specified volumes and concentrations of solutions.

7. Reading and Recording Volumes We use significant figures to indicate the accuracy and precision of glassware. Significant figures for graduated glassware are determined differently from those of volumetric glassware.

8. Significant Figures: Volumetric Glassware Use the Tolerance table on p. 65 to determine glassware tolerance, unless it is printed on the glassware. For example: The 50 mL volumetric flask has a tolerance of ± 0.05 mL. Whenever you use your 50 mL volumetric flask, you will always report two zeros after the decimal, i.e. 50.00 mL.

9. Volumetric Flask When this volumetric flask is filled to the calibration mark, what volume should be reported?

10. Volumetric Pipet When this pipet is used to dispense solution, what volume should be reported?

11. Volumetric Pipet When this pipet is used to dispense solution, what volume should be reported? And to which line should the pipet be filled?

12. Significant Figures: Graduated Glassware 1. Look at the glassware in question. 2. Find the smallest graduation. 3. Report your volume to the closest 10% of the smallest graduation.

13. Reading Graduated Glassware

19. Smallest Graduation A. Calculate major graduation – major graduation B. Determine the number of spaces between two major graduations Smallest Graduation = A / B

20. Reading Beakers What volume should be reported?

21. Reading Beakers Smallest graduation: 10 mL 10% value: 1 mL Volume to the closest 10% of the SG: 48 mL

22. Reading Graduated Cylinders What volume should be reported?

23. Reading Graduated Cylinders Smallest graduation: 1 mL 10% value: 0.1 mL Volume to the closest 10% of the SG: 52.8 mL

24. Reading Burets What volume should be reported?

25. Reading Burets Smallest graduation: 0.1 mL 10% value: 0.01 mL Volume to the closest 10% of the SG: 40.05 mL

26. Cleaning Glassware Each student has glassware at their individual stations. Each student is responsible for the care of their glassware. Why do we start and finish each experiment with clean glassware? Your instructor will address the appropriate ways to: Wash glassware with soap and a brush Rinse glassware with tap water Do a final rinse with very little distilled water from the distilled water faucet or from your water bottle Dry your glassware Return glassware to the APPROPRIATE drawer

27. Using a Digital Thermometer Carefully remove your digital thermometer from your glassware drawer. We use digital thermometers in lab to determine the temperature of solutions. Our digital thermometers can measure temperature in degrees Celsius (ºC) or degrees Fahrenheit (ºF). Eventually you should be able to interconvert between these two scales. Kelvin will also be addressed in class. Your instructor will point out all major features of this unit.

28. Glassware The use of many pieces of glassware is intuitive. You will not be shown how to use a beaker, graduated cylinder, medicine dropper, or filtering flask. Other pieces of glassware are highly specialized. You will now be shown how to properly prepare and utilize the following pieces of glassware: Analytical balance Buret Volumetric flask Volumetric pipet

29. Experimental Procedure and Report Follow the instructions starting on page 72. Record your responses starting on page 85. Do not leave the lab until you have followed all of the instructions under Part 7.

30. Next Assignment: Lab 3 Read the required reading sections in your textbook and lab manual. Complete and submit your pre-lab questions by the deadline. Remember to study for your next quiz. Submit the Lab 2 report at the start of the next lab.

31. Lab 4 Pre-lab Questions This pre-lab will take a while to complete, start early. Read the lab write-up in your manual (pp 109 - 134). Complete the pre-lab questions (pp. 109 - 134) in MicroLab™ in the SCICom lab (NSB 204), Chemistry Resource Center (CPSB 302K) or on your personal computer if you download the program. The program may be downloaded from http://www.microlabinfo.com under the Downloads link.http://www.microlabinfo.com Take this exercise seriously. You will be required to complete a similar exercise in lab in 2 weeks without help from your lab manual.