Introduction to Physical Science/1.1

Writing Laboratory Reports

When a scientific experiment is performed, all its parts are carefully recorded, and all data gathered is diligently organized. In this section, we will discuss the basic elements of a laboratory report and how to effectively write for a scientific report.

Title

All labs must be named, and therefore the first part of a lab is its title and the number of the section.

Purpose

It is important to ask the question: why is this lab important? The purpose of a lab is a question to be answered.

Example: In a lab about the density of copper the purpose might read: what is the density of copper?

Hypothesis

If it is at all possible, it is important to record a hypothesis prior to performing the experiment. A hypothesis is an educated "guess" as to the outcome of the experiment. Creating a hypothesis allows us to see how far away from the truth our original ideas where (if anything but the truth).

Materials

Keep a detailed list of all materials used in the experiment. This will allow you to make sure nothing is missing when you actually construct and perform the experiment. Keeping a list such as this would allow another person to repeat your experiment in order to test your results. The ability of an experiment to be repeated is considered a good quality in science.

Diagram

It is important to sketch a small diagram of all materials used in the experiment to demonstrate how they will be set up when the experiment is performed.

Procedure

This is possibly the most important section of all. The procedure is a list of numbered instructions that tell how an experiment is done. The procedure should be clear, concise, and very easy to read. The procedure steps should be simple. Each step should be about a sentence in length. The procedure in each experiment should be written so that a person who has little or no knowledge of science or of the experiment you are performing could do it with no preparation.

Data

Data is the product of following an experiment's procedure. Data is most frequently collected in tables at first because they are easy to use and they present data in an easily recognizable format. A data table has several parts. In lesson 1.2 we will talk about the use of data tables and the collection of data.

Graphs and Charts

Graphs and charts are a more visual way of representing data. We will talk about different types of Charts and Graphs in chapter 1.4.

Conclusion

The conclusion is a short paragraph that discusses the outcome of the lab, what was gained from the lab, and what could be done differently and/or changed. The conclusion reviews the procedure and attempts to answer the purpose question. If no answer can be reached, then explain why the purpose question was not answered and explain what further work might answer it.

Vocabulary and Questions

• Labs are experiments done in a laboratory environment.
• Data is the information gained from an experiment.
• Tables are a graphic way of organizing data, also known as a chart.
• Graphs are another way of representing data, but instead of using words it uses pictures.
• Hypothesis is an educated guess as to what may happen when the experiment is performed.

Covering The Reading

1. What part of the experiment would you suggest changes to the procedure?
2. Which section would you collect data in?
3. What does the word lab denote?
4. When writing a lab procedure what should be remembered about the instructions?
5. If you have a lab that is about the solubility of citric acid what would be a valid purpose?