Example of formal lab report
I. Problem: Using Tide, Cheer, and Surf, which brand of laundry detergent will decrease the diameter of the mud stain?
II. Research: Not required for this lab
III. Hypothesis: If a white t-shirt with a 5 cm mud stain is washed in Tide, Cheer, and Surf, then Tide will reduce the diameter of the mud stain.
IV. Experiment:
A. Variables:
1. Independent variable- brand of laundry detergent
2. Dependent variable- diameter of mud stain
3. Control- t-shirt washed in water only
4. Constants- washing machine, t-shirt (color, brand, and size), type of
mud, same of detergent, same type of detergent (liquid, powder or pod),
temperature of water, cycle on washing machine, same cookie cutter
B. Materials:
1. 4 white t-shirts
2. 25 g of mud for each shirt
3. Mud (1 bag of potting soil and 30 L of water—mix well)
4. 25 mL of liquid Tide, Cheer, and Surf detergent
5. Washing Machine
6. Circle cookie cutter
7. Metric ruler
C. Procedures:
1. Mix the mud
2. Measure and mark placement of stain (beneath the neck in the center of
the t-shirt)
3. Measure 25 g of mud
4. Place cookie cutter on marked area of t-shirt, fill with mud, and
carefully remove the cookie cutter
5. Measure the diameter (  5 cm)
6. Place the t-shirt in washing machine on normal cycle using cold water
only (don’t add detergent on first trial—this is the control)
7. When washer finishes, immediately remove t-shirt
8. Measure diameter of stain and record (record observations)
9. Repeat steps 2-8 on remaining shirts

D. Data:
Laundry Detergent
(Brand)
A- Water only
Brand of Detergent VS Diameter of Mud Stain
B- Tide
C- Cheer
D- Surf
Diameter of mud stain
(cm)
5
3
2
4
Observations made
Color of stain did not appear to change; the diameter of the mud stain remained the same
Color faded slightly when compared to shirt A; the diameter decreased by 2 cm
Color had the greatest change compared to shirt
A; the diameter decreased by 3 cm
Color had the second greatest change compared to shirt A; the diameter decreased by 1 cm
E. Results:
The t-shirt washed in Cheer had a decrease of 3 cm in the diameter of the mud stain.
This shirt also had the greatest observable color change compared to shirt A. Tide decreased the diameter of the mud stain by 2 cm but had very little observable color change when compared to shirt A. Surf decreased the diameter of the mud stain by 1 cm yet had the second best observable color change when compared to shirt A. The t-shirt washed in water only had no significant affect on the diameter or color of the mud stain.
V. Conclusion:
A. If t-shirts are washed in Tide, Cheer, and Surf, then Tide will reduce the diameter of
the mud stain the most.
B. The hypothesis was not supported because Cheer had the greatest reduction in the
diameter of the mud stain.
C. Cheer reduced the mud stain from 5 cm to 2 cm with the greatest observable color
change when compared to shirt A.
D. Repeat the test more than once for each detergent.
E. Based on the data, I learned that Cheer worked best on the diameter of the mud stain.
To improve this experiment, I would repeat the test 5-10 times for each detergent.