FIRST D[JT1]AY IN THE LABORATORY
Preliminary Reading
Before coming to the laboratory, read the syllabus, the material on safety, cleanliness, and consideration (pp. 1-4), on records and reports (pp. 5-7), and on laboratory grading policies (pp. 43-46) in the introductory section of this laboratory manual. Also read the material on weighing (pp. 25-27). Instruction on the use of the electronic analytical balances will be given in the laboratory.
Orientation
A brief orientation to the organization of the lab will be given at the beginning of the period and you will be divided into two groups, I and II. After the Orientation, Group I will proceed directly to the laboratory and complete the Check-In and Weighing exercises. Group II will proceed to the computer lab, Room 113, and will be introduced to Excel. The Excel portion of the period is covered by the document Introduction to Computing and Excel. At 15:15, the two groups will switch.
Laboratory Desks & Check-In Procedures
Each student will be provided with a desk "locker" containing the common laboratory items needed throughout the course of the year. Check the contents of your locker against the list provided for this purpose. If any items are missing or damaged, obtain replacements from the stockroom. Check your glassware carefully for small flaws such as chipped pipet and buret tips, star cracks in flasks and beakers, and chipped lips on beakers and graduated cylinders. Rubber goods should be checked for flexibility and serious cracking. It is important that you check your desk contents very carefully now, for when you check out of the laboratory at the end of the course, you will be expected to leave the desk contents in first-class condition, with damaged or missing items at that time being billed to your account. When you are finished checking your desk, turn in your signed list and account card at the Chemistry Stockroom and obtain the key to your desk. For certain experiments, additional or special glassware or equipment may be required. These will be signed out from the stockroom and returned at the end of the lab period. Students will also be charged for loss or breakage of these "special" items. During the course of the year, you may be required to store solutions or samples from one week to the next. All such items must be clearly labeled with your name, lab period, and the chemical name(s) of the contents.
Balance Instruction and Practice
After instruction on use of the electronic analytical balances you will be given a numbered glass rod to use in practicing the weighing of objects on the electronic analytical balances. Enter the data in the report sheet and give the report sheet to the teaching assistant when you are through with your weighing practice.
Weigh the glass rod five independent times; that is, remove the glass rod from the balance pan and check the balance zero for each weighing. To familiarize yourself with the tare feature of the balance, first weigh a 50-ml beaker; then weigh the beaker with the glass rod in it. Obviously the weight of the glass rod is the difference between these two weighings. Now place the beaker on the balance pan and press the red T (tare). The balance should read zero again. Place the glass rod in the beaker and read the weight of the glass rod. Compare all of your weights for the glass rod. If your agreement among the weights is not satisfactory, check with the teaching assistant or instructor.
WES, 1stday_51.doc, 29 Aug. 2002
Name______Lab Section______
Date Report Submitted______
FIRST DAY IN THE LABORATORY
Glass Rod No. ______Balance No. ______
1.Weight of Glass Rod
1. ______
2. ______
3. ______
4. ______
5. ______
Average______
2.Weight of Glass Rod Weighed in a Beaker.
Weight of Beaker + Rod ______
Weight of Beaker ______
Weight of Rod ______
3.Weight of Glass Rod Using Taring Feature
Weight of Rod ______
1
[JT1]1This section has been modified to account for the fact that we are not checking in lockers this year due to the renovation. The "original" document including check-in procedures can be found in firstday.doc in the masters chem1a lab manual99 folder.