Beacon Lesson Plan Library

Solving a Problem with the Scientific Method

Tracy Wade


Students will use the scientific method to determine the similarity or difference in 2 liquids.


The student knows that investigations are conducted to explore new phenomena, to check on previous results, to test how well a theory predicts, and to compare different theories.

The student knows that scientists control conditions in order to obtain evidence, but when that is not possible for practical or ethical reasons, they try to observe a wide range of natural occurrences to discern patterns.

The student knows that technological problems often create a demand for new scientific knowledge and that new technologies make it possible for scientists to extend their research in a way that advances science.

The student knows that scientific knowledge is used by those who engage in design and technology to solve practical problems, taking human values and limitations into account.


2 liquids (mixture instruction are on the attached file)
Erlenmeyer flasks containing liquids
2 stoppers
clock or watch with second hand
1000mL beaker


Gather Materials
Make copies of worksheet
Mix up solutions per attached instructions


Part A.
-Examine the two flasks. DO NOT remove the stoppers and DO NOT shake the contents. Notice the flasks have been labeled A and B. Record ,in a table, two or three similarities or differences between the two flasks. Do Part A of the attached worksheet.

Part B. Experimentation
Experiment 1
-Give each flask ONE HARD SHAKE using an up and down motion. Make sure your thumb covers the stopper as you shake. Observe each flask carefully. Record your obersvations in table. Answer the questions on Part B-Experiment 1 of the worksheet.

Experiment 2.
-Remove the stopper from flask B and pour out half of the contents into a beaker. Replace the stopper. Give both flasks ONE HARD SHAKE using an up and down motion. Observe each flask carefully. Record any similarities or differences in Table . Answer questions on Part B-Experiment 2 of the worksheet.

Experiment 3
-Shake each flask HARD once in an up and down motion. Note the EXACT TIME in seconds after shaking that it takes for each liquid to return to its original condition. Record tke time in Table .
Shake each flask HARD TWICE with and up and down motion. Again record in Table the time it takes for the liquids to return to their original conditions.
Shake each flask HARD THREE TIMES with an up and down motion. Again record in Table the time it takes for the liquids to return to their original conditions.
Answer the questions on the worksheet pertaining to Part B- Experiment 3.
Run two or three more trials for each part of Experiment 3. Consider your recorded results in Table and answer the questions on the worksheet.

Experiment 4
-Remove the stoppers from both flasks and give each flask ONE HARD SHAKE. Remember to keep your thumb on the stopper as you shake.

PART C. Interpretations
-Think carefully about what you have observed and answer the questions on Part C of the worksheet.

Part D. Hypothesis Formation
-Consider the original problems and the experiments conducted, Write a hypothesis which attempts to explain the following:
a) why the liquid in flask B did not change when the flask was filled completely with the liquid.
b) why the liquid in flask B changed when the flask was only half filled.
c) why is it important that shaking occur in both flasks A and B.
d) why the liquids in flasks A and B would take longer to change back to their original color with more shaking.


Evaluate students work on the attached worksheet and determine their understanding of procedure. Correct answers on worksheet will verify their understanding.
Teacher's observation of student's lab skills

Attached Files

Instructions for solutions and copy of worksheet.     File Extension: pdf

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