Sample Lab Report - Download as DOC - DOC

							                                                      Sample Lab Report

Advertisements for household products pose numerous questions for investigation--for example, advertisements for effervescent
tablets (Alka-Seltzer) that reduce stomach acid. The tablets go plop, plop, fizz, fizz. Students in the scenario below were
challenged to determine whether the temperature of the water affects the solubility (how well they dissolve) of the tablets.

Below is an example of a lab report that resulted from students designing and performing an experiment based on the information
above. Use this sample to develop your own lab report.

TITLE:
The Effect of Water Temperature on the Dissolving Time of Effervescent Tablets

INTRODUCTION:
This should be written in paragraph form. Three guiding questions should provide framework for the introduction.

Question 1: Why did you conduct the experiment? (This is your RATIONALE.)
Some over-the-counter drugs are effervescent tablets that must be dissolved in water before ingestion. Directions do not include
specific water temperatures.

Question 2: What did you hope to learn? (This is your PURPOSE.)
The purpose of this experiment was to determine the effect of water temperature on the time required for effervescent tablets to
dissolve.

Questions 3: What did you think would happen? (This is your HYPOTHESIS—written in if, then format.)
The researcher hypothesized that if the temperature of the water is increased, then effervescent tablets will dissolve faster.

NOTE: In your report, the italicized sentences above would appear as a single paragraph. The questions are included above just to
guide your thinking.

EXPERIMENTAL DESIGN:

IV: Temperature of Water
           Cold                                      Room                                Hot
                                                   (Control)
             5 Trials                               5 Trials                           5 Trials
DV:       Time to Dissolve (sec)
C:        Brand of tablet (Alka-Seltzer)
          Amount of water (75 mL)
          No Stirring
          Type of Cup

PROCEDURE:
A list of EVERY step necessary to carry out the investigation. Someone should be able to carry out the investigation from reading
your procedure. Include all quantities and all safety concerns.

1.    Place one Alka-Seltzer brand tablet in a plastic cup containing 75 ml of cold water.
2.    Record the amount of time, in seconds, it takes the tablet to completely dissolve.
3.    Repeat steps 1 & 2 five times.
4.    Repeat steps 1 – 3 with room temperature water.
5.    Repeat steps 1 – 3 with hot water.
6.    Calculate the mean (average) dissolving at each temperature.
RESULTS:

                                                           Figure 1. Data Table

  Temperature of                                       Time to dissolve (sec)           Average time to
     Water                                                    Trials                     dissolve (sec)
                                                   1     2       3      4         5
                               Ice                  98   104    107      96       105        102
                              Room                  43    35      46     46        30         40
                               Hot                  24    27      19     19        27         23

                                     Figure 2. Bar Graph


                             125
    Time to dissolve (sec)




                             100
                             75
                             50
                             25
                              0
                                     Ice          Room          Hot
                                           Water Tem perature




CONCLUSION:
The conclusion requires a thinking process that involves both the analysis of data and the discovery of relationships. Below you
will find an organization framework for guiding this though process. As with the introduction, this section should be written in
paragraph form—using the following questions to guide and organize your thoughts.

What is the purpose of the experiment?
The purpose of this experiment was to determine the effect of water temperature on the dissolving time of Alka-Seltzer tablets.

What were the major findings?
At higher temperatures, Alka-Seltzer tablets dissolved faster. For each rise in temperature, dissolving time was further reduced.
NOTE: Please notice that the researcher DID NOT just restate the data. He found the general relationship between the
temperature of the water and the dissolving time.

Was the research hypothesis supported by the data?
The data supported the research hypothesis that Alka-Seltzer tablets would dissolve faster in warm water than in cold water.
NOTE: A hypothesis is not proved or disproved by a single experiment. The data either supports or fails to support the
hypothesis.

How did your findings compare with other researchers or with information in the textbook?
The findings agree with the solubility rule that solids dissolve faster in warm solvents.

What possible explanations can you offer for the findings?
Because molecules move faster in warm water, they would strike the tablet more frequently and tear it apart more quickly.

What recommendations do you have for further study and for improving the experiment?
Additional experiments could be conducted to determine the dissolving rate of other brands of tablets. The experiment could be
improved by insulating the cups to reduce heat exchange with the room.


**Above material developed from ideas in Students and Research by Julia Cothron, Ronald Giese, and Richard Rezba
(Kendall/Hunt Publishing Co., Dubuque, IA, 2000).