General format and structure of a lab report: tips and sample

The lab reports are the most frequent form of writings in engineering. Professors always want something different from you but the goal of writing a lab report remains the same. The general format and structure of lab report is under

  • Title Page

The title page contains the name of the experiment, name of the writer and date. A title page should be clear and informative


  • Abstract

Abstract has the summary of your report. It explains the main points of discussion and result. An abstract should not be more than one paragraph


  • Introduction

It states the objective of the experiment and provides the background of an experiment. A good introduction provides the background theory and research.


  • Methods

In this section, you explain the methods material and types of equipment used. you simply list all these things


  • Experimental Procedure

Describes the process in chronological order. Using clear paragraph structure, explain all steps in the order they actually happened, not as they were supposed to happen


  • Results

Results are dominated by calculations, tables, and figures. You have to explain all the things in order to make the reader understand


  • Discussion and Conclusion

Is the most important part of your report, because here, you show that you understand the experiment, conclusion is very short and comprehensive. You give your opinion and recommendations in this section


  • References

You list all the references that you have used for your experiment.


Sample Lab Report

The sample lab report is presented as under. This sample is taken from internet in order to make our readers understand, how lab reports are written. This is an experiment about the temperature and pressure measurements of an ideal gas.

Temperature and Pressure Measurements of an Ideal Gas
That Is Heated in a Closed Container 


This report discusses an experiment to study the relationship of temperature and pressure of an ideal gas (air) that was heated in a closed container. Because the ideal gas was in a closed container, its volume remained constant. The objective of the experiment is to test whether the ideal equation of state holds. In the equation,

pV = MRT,

where p is the pressure the gas, V is the volume, m is the mass, R is a constant, and T is temperature. This report presents the procedures for the experiment, the experiment’s results, and an analysis of those results.


In this experiment, air (an ideal gas) was heated in a pressure vessel with a volume of 1 liter. Attached to this pressure vessel was a pressure transducer and thermocouple to measure the pressure and the temperature, respectively, of the air inside the vessel. Both of these transducers produced voltage signals (in Volts) that were calibrated to the pressure (kPa) and temperature (K) of the air (the atmospheric pressure for where the experiment occurred is assumed to be 13.6 psia). In addition, the theoretical temperature (K) of air was calculated as a function of the measured pressured values (kPa).

Results and Discussion

This section analyses the results of the experiment. The experiment went as expected with no unusual events that would have introduced error. The voltages as measured for the pressure and temperature transducers appear in Table A-1 of the Appendix. Also included in the Appendix are the equations used for calibrating those voltages with the actual pressures and temperatures. These equations led to the values of pressure and temperature that are shown the third and fourth columns of Table A-1. From these values, a graph between temperature (K) and pressure (kPa) was created (Figure A-1). As can be seen from the graph, the relationship of temperature versus pressure is roughly linear.

As part of this experiment, the theoretical values of temperature were calculated for each measured pressure value. In this calculation, which used the ideal gas equation, the volume and mass were assumed to be constant. These theoretical values of temperature are shown in the final column of Table A-1. From this final column arose Figure A-2, a graph of ideal temperature (K) versus pressure (kPa). As shown in this graph, the relationship between temperature and pressure is exactly linear.

A comparison between the graph showing measured data (Figure A-1) and the graph showing theoretical data (Figure A-2) reveals differences. In general, the measured values of temperature are lower than the ideal values, and the measured values are not exactly linear. Several errors could explain the differences: precision errors in the pressure transducer and the thermocouple; bias errors in the calibration curve for the pressure transducer and the thermocouple; and imprecision in the atmospheric pressure assumed for the locale. The bias errors might arise from the large temperature range considered. Given that the temperature and pressure ranges are large, the calibration equations between the voltage signals and the actual temperatures and pressures might not be precise for that entire range. The last type of error mentioned the error in the atmospheric error for the locale where the experiment occurred is a bias error that could be quite significant, depending on the difference in conditions between the time of the experiment and the time that the reference measurement was made.


Overall, the experiment succeeded in showing that temperature and pressure for an ideal gas at constant volume and mass follow the relation of the ideal gas equation. Differences existed in the experimental graph of temperature versus and pressure and the theoretical curve of temperature versus pressure. These differences, however, can be accounted for by experimental error.