CHM 1025C/CHM 1032C

Welcome to the Chemistry Lab D-204

Introduction

The experiments in this lab manual have been chosen to introduce you to some basic and important laboratory equipment and techniques. In addition, some of the experiments provide an opportunity for you to test your laboratory skills by analyzing “unknown” samples. Each experiment is designed to be completed within a two-hour period. You should be able to complete the work in the time allotted. This time allotment does assume, however, that before coming to the laboratory you have read the introduction to the experiment, have answered the pre-laboratory problems (which introduce needed concepts), and have carefully read the experimental procedure.

Laboratory Notebook and Reports

Student Must purchase a Laboratory Research Notebook in the bookstore, ISBN #r 9781930882508 for ~$14. All students must use this Notebook. This notebook has NCR duplicate pages. One page will remain in your notebook as a permanent copy, the other is designed to be torn out and submitted to your instructor. A lab report must be submitted for each experiment that you perform.

For most experiments, the report will be in three parts:

(1) the pre-lab due at the beginning of the lab period,

(2) the data and observations collected while in the lab, and

(3) the calculations and post-lab questions to be completed after the procedure.

The majority of the labs in this manual have a data recording and report sheet created for you to copy in your Laboratory Research Notebook as part of your pre-Lab Activity. If no report sheet is provided, you must create your own in your laboratory notebook.

All submitted recordings and reports must be neatly handwritten, and should contain the following elements, when applicable, in the order given:

Pre Lab (do NOT tear out your pre-Lab report from your notebook unless directed to do so. Your instructor will initial your pre-lab report during the beginning of lab):

1. Your name, section number, and date.

2. The title of the experiment and the date on which it is performed.

3. Answers to any pre-lab problems must be written in your notebook. Then the actual data recording page must be neatly laid out in your notebook.

Data and Observations:

4. All data and observations are to be entered directly into your notebook as you go through the experiment. Each student must record his/her own data. Do not use a sheet of paper and then transcribe the data into the notebook later. Do not record data in any datasheet you are given. Neatness is important, but honesty and accuracy are equally as important.

Numerical data must be identified by a tag (e.g. “mass of Erlenmeyer flask – empty”) and include units (g, mL, etc.). Use the correct number of significant figures to report your data.

For example:

Mass of empty Erlenmeyer flask 52.650 g

Mass of flask + benzoic acid 53.492 g

Note that you record both masses, not just the difference between the two. Similarly, for measurements with a buret, you should record both the initial and final buret readings, not just the difference between them. See the sample Data Recording Sheet provided with the experiment. (You first two buret readings must be initialized by your instructor as with many of your other first reading with measuring equipment.)

All data is to be entered in ink; no pencils and no erasures. If an error is made in recording data, draw a single line through the mistake, correct it nearby and initial the correction. Do not obliterate any entry. If a substantial portion of a page is to be discarded, cross the material out with an X.

Neatness and care in recording data and calculations are a plus, but it is more important that the notebook be an immediate and permanent record, “warts and all”, of everything that happened in the lab.

Turn in your duplicates with your report.

NOTEBOOK ORGANIZATION

5. Title Page: List your name, address and phone number along with the course section and instructor name.

Table of Contents: Leave one or two pages blank to fill in the list of experiments as you go. List the date, title and beginning page number of each experiment. You will turn this in at the end of the semester

Before coming to the lab, read the experiment to be done and do the prelab exercises. In your notebook, write a title and the date of the experiment, a brief statement of purpose. Make notes in your notebook and work out a tentative procedure and data tables to be filled in. This is called “preparing your notebook to accept data” and will save you time as well as organizing your thinking. It is usually not possible to anticipate everything. Make any corrections and additional observations as you work through the lab.

Safety Lab or Experiment #1 Organization

a. On page 4 of your lab manual will begin the Safety Lab. At the top of the page place your name, section number and the date. Then, place the title: Safety Lab

b. Then place a subheading: ACS Safety Film Notes:
As you watch the film, record notes or emphasized statements which will become a rough set of safety rules.

c. Make a rough sketch of the room in your notebook. Label on the sketch the following: Safety shower, emergency eyewash, safety blanket, goggle/glasses cabinet, first aide kit, two major wash up sinks for hand washing and hardware equipment drawers identified by the instructor.

d. On a new page as a post lab report, list at least 20 lab safety rules from the three handouts and the ACS film. At the bottom, copy the lab safety contract and sign it.

e. On the separate page of your lab notebook Sketch the NFPA symbol and then copy a more detailed or specific hazard for each NFPA category from the Safety Codes handout. Explain what each number represents in each category

f. In your lab notebook sketch the HMIS Labeling System and list the descriptions for each number for each category.

g. In your lab notebook, state the purpose behind both system and why they are different.

h. Using Chemical Date Bases on the Internet, copy on a new page in your notebook the data sheet from the MSDS Assignment handout and fill in the form for the chemical assigned and submit this page by the second lab period.

(Instructor’s note: Safety Lab will be the longest report in this course as it requires a lot of copying of information you may need during a lab and/or handling chemicals. Most reports are usually only one, two or three pages in length depending on the calculations.)

Final Report – Non Formal:

6. If you have copied a printed report sheet from this manual you have two copies in your research notebook. Include a copy of this data and its summary in your final report. Also include your name, section number, and date on every page.

7. Calculations: There should be a separate section devoted to the calculations unless the data report sheet has left room for a simple calculation, such as the Density Lab. Otherwise, the calculations should be completely separate from your data and results. You must show every mathematical calculation that you perform.

8. Answers to any Post Lab questions and/or conclusions belong on separate page in your notebook unless ample room is obviously provided.

Final REPORTS – Formal:

Most of labs include a datasheet that will serve as your non formal report. However there will at least one lab, usually the last week, requiring a more formal report. The following format should be used.

A. Title: the name and number of the experiment, name of your lab partner(s), if any, and the dates of the experiment and of the report.

B. Purpose or Abstract: a statement describing the major goals of the experiment.

C. Procedure: describe how you went about the experiment. Usually a reference to the handout will suffice; however, you should mention any changes or deviation from the procedure as given to you. Rewriting the whole procedure is an unnecessary duplication of effort.

D. Data: record, in tabular format where possible, all pertinent data collected, calculated values and results. It is often appropriate to have two tables, one for original data and another for results.

E. Calculations: show equations and calculations used to arrive at final results. A general formula and one example are sufficient for repetitive calculations. Include here any required graphs.

F. Conclusions: discuss the results of the experiment and how they relate to the concepts in the reading material. Was the stated purpose achieved? If not, why not? Include a discussion of major possible errors and their impact on the experiment. The conclusion section is the most important part of the report and has the most influence on your grade. The prelab mini-lecture will give you information about the important points of the lab. Listen carefully and take notes.

G. Post-lab: Answer any questions or exercises included as part of the experiment.

9. Pre and Post Lab calculations are designed to be performed individually, with the answers given to the correct number of significant figures and with the correct units.

10. Pre and Post Lab questions are designed to be answered individually. Answers should be concise, legible, and in your own words (do not plagiarize or otherwise copy from texts, websites, or your classmates).