Homework Assignment 01...is from Chapter 1. Problems assigned are: 4,5,9,10,12,15,22,29,31 (pages 29 ff) This assignment is due at class time Friday, Sept 10 Prepare on regularly sized paper, one side only with multiple pages stapled. __________________________________________ Homework Assignment 01

__________________________________________ Chapter 2 – Tools of the Trade Analytical Balances The actual mass of an object as measured in a vacuum is usually greater than the apparent mass measured in air due to the buoyancy effect. We will not apply buoyancy corrections to the masses measured in this course.

__________________________________________ Chapter 2 – Tools of the Trade Volumetric Glassware Volumetric glass-ware a) a 50-mL glass buret and b) a digital titrator

__________________________________________ Chapter 2 – Tools of the Trade Volumetric Glassware The glass buret is directly readable to 0.1 mL. You will subdivide the finest graduate marks by 10 to read the buret to 0.01 mL. The meniscus is read at the bottom of the curve, except for dark colored solutions such as iodine or permanganate.

__________________________________________ Chapter 2 – Tools of the Trade Volumetric Glassware Be sure to work the air bubble out of the area between the stopcock and the tip before proceeding to titrate.

__________________________________________ Chapter 2 – Tools of the Trade Volumetric Glassware Various forms of volumetric flasks. They also come in sizes from 2-L down to 1-mL

__________________________________________ Chapter 2 – Tools of the Trade Volumetric Glassware The meniscus of the neck of the volumetric flask needs to be adjusted very carefully. I suggest using a dropper. The area above must be clean so that drops of solvent will not add to the total volume.

__________________________________________ Chapter 2 – Tools of the Trade Volumetric Glassware Pipets come a variety of forms. a) 10-mL transfer pipet (TD) drain b) graduated pipet transfer pipet (TD) drain c) Ostwald-Folin 5-mL pipet (TC) blow out d) Serological graduated pipet (TC) blow out

__________________________________________ Chapter 2 – Tools of the Trade Volumetric Glassware Microliter pipets

__________________________________________ Chapter 2 – Tools of the Trade Volumetric Glassware a) Glass  -liter syringe and b) digital dispenser for microsyringes

__________________________________________ Chapter 2 – Tools of the Trade Filtering Techniques Filtration with a Gooch crucible. You will use a plastic check valve in place of the trap (right-most flask).

__________________________________________ Chapter 2 – Tools of the Trade Filtering Techniques Folding filter paper to use with conical glass funnels

__________________________________________ Chapter 2 – Tools of the Trade Filtering Techniques Quantitatively transferring the precipitate and solution onto the filter. The procedure is the similar anytime you are doing a quantitative transfer of a solution.

__________________________________________ Chapter 2 – Tools of the Trade Miscellaneous Lab Techniques Protecting drying samples or standards in the oven

__________________________________________ Chapter 2 – Tools of the Trade Miscellaneous Lab Techniques The desiccator provides for protection of materials that have been dried from the absorption of water vapor. b) is a vacuum desiccator

__________________________________________ Chapter 2 – Tools of the Trade Miscellaneous Lab Techniques Glassware may be calibrated by measuring the mass of water contained in or delivered by the glassware. Since density = mass/volume, the volume is calculated. For exact work the temperature is also measured and the density at a given temperature used. The density as a function of temperature may be obtained from the CRC Handbook.

__________________________________________ Chapter 2 – Tools of the Trade Miscellaneous Lab Techniques The microwave digestion bomb lined with Telfon used to decompose organic samples