Ertt
By: lkk25598 • Essay • 578 Words • May 13, 2011 • 1,801 Views
Ertt
List the molecular weight, melting point, boiling point, density, solubility, and hazards of all pertinent chemicals used in the experiment. You can find this information in the CRC Handbook of Chemistry and Physics. (We have this book at school, and a CD-ROM version as well.) Or, you can find the information on the Internet (see: Hazard and Physical Data for Compounds page). Chemfinder.com is an excellent site to find this data. The physical data are most conveniently presented in tabular form, although in a preparative experiment you may put the amounts of reactants and products under the balanced equations for the reaction.
Calculate the amounts of reactants (or compounds to be purified) in moles and grams or mL (as applicable). In a preparative experiment, calculate the limiting reagent and the theoretical yield of the product. Be sure to include your calculations for these values.
Procedure
Briefly summarize the procedure to be followed, preferably either as an outline or as a flow chart. You do not need to write out the procedure in complete sentences and do not copy directly from the Lab Manual. All you need is a brief but complete listing of what you plan to do in the lab. The first time you do a technique, such as distillation, include in the procedure section a description of how to assemble the apparatus and how to conduct the distillation. In later experiments, it will be sufficient to state only that the liquid was distilled.
Data and Observations
Your observations of the experiment as it progresses is important, new information. Write these observations (color changes, appearance of crystals, formation of an emulsion, boiling temperatures, test results, etc.) in your notebook as you do the experiment. Also record the weights of reagents and products and tare weights in this section.
In general, you do not need to re-write the Procedure section in these observations, instead, you may state that "the procedure was carried out as planned" or "the procedure was carried out as planned except . . . ." At times, however, you may have to write the procedure out partially. For instance, if you state "the solution