Transcript Scientific Method - Helen Keller Junior High School

Film Canister Lab
There are many ways to conduct
science
Examples:
 Observational- Field study
 Such as animal behavior

“Experimental Research” – Conducts
controlled experiments.
 Tests one variable
 Different steps
One way of researching the natural world
Identify a Question or Purpose
After observing the world around you, you can
derive a problem that you want to find more
about
Observation: Plants grow taller in sunnier areas.

Derive a question based on observation above
that you would like to investigate.
AND/OR
State purpose of experiment
 Purpose Statement: Communicates what your
experiment is about.

Flip Book- Purpose Question
Rationale
Gives focus to the investigation
My Responsibility
Read for understanding
Format
Purpose: Statement or question
Example
Purpose: Does the amount of
light a plant receives effect the
height of the plant?
OR
Purpose: The purpose of this
research is to determine the
effect of the amount of sunlight
on the height of plants.
Observation of film canister
Get out piece of clean loose leaf paper
and a pencil
 Teacher demo

NO TALKING
LISTEN AND WATCH
TEACHER
Film Canister LabPurpose :
Does changing the amount of water in
the film canister change the reaction
time?
Background Information

Scientist research and become
knowledgeable about the subject and
investigation that they are going to test.
 They know and understand key concepts
relating to their topic .
AND/OR
 They know and understand other
investigations that have already been
conducted about their topic.
Flip Book- Background info
Rationale
Provide facts to understand the
investigation
My Responsibility
• Read
• Take notes and highlight
• Make connections
Format
Background Information: Paragraph
of information
Example
Organisms need energy to survive.
Some organisms are capable of
absorbing energy from sunlight and
using it to produce sugar and other
organic compounds such as lipids
and proteins. The sugars are then
used to provide energy for the
organism. This process, called
photosynthesis, is used by plants
and some protists, bacteria, and
blue-green algae.
Background Information
There's nothing like a little rocket science to add some
excitement to the day. Alka-Seltzer (an effervescence) is made of
sodium bicarbonate (baking soda), citric acid, and acetylsalicylic acid
(aspirin). When you add water it starts to dissolve the Alka-Seltzer
tablet. When the solid dry powders of sodium bicarbonate, citric acid,
and acetylsalicylic acid are pressed together to make a tablet, being
solids, the molecules are not mobile enough to react. Adding water
dissolves them and allows them to mingle and react. This creates a gas
called carbon dioxide. As the carbon dioxide is being released, it creates
pressure inside the film canister. The more gas that is made, the more
pressure builds up until the cap it blasted down and the canister is
blasted up. The lid of the canister is the path of least resistance for the
gas pressure building up inside, so it pops off instead of the stronger
sides or bottom of the canister bursting open. We can thank Sir Isaac
Newton for what happens next. When the build up of carbon dioxide gas
is too great and the lid pops off, Newton's Third Law explains why the
film canister flies across the room: for every action there is an equal and
opposite reaction. The lid goes one way and the film canister shoots out
of the tube in the opposite direction. This system of thrust is how a real
rocket works whether it is in outer space or here in the earth's
atmosphere. Of course, real rockets use rocket fuel.
Film Canister- Background Info
Cut and Glue in the Background information
for the Film Canister Lab onto your Lab
Paper.

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Example Things I Highlighted/Underlined
There is a chemical reaction that happens between
an acetylsalicylic acid and a sodium bicarbonate.
The reaction produces a gas (carbon dioxide).
The canister is sealed so the gas builds up inside the
canister creating pressure.
When there is too much pressure inside the canister,
it needs to go somewhere so the cap pops off
because it is the path of least resistance.
Demonstrates Newton’s third law
Demonstrates how thrust works
Hypothesis
A HYPOTHESIS is a tentative statement
that proposes a possible explanation to
some phenomenon or event.
 A hypothesis:

 Is written in an IF…Then … Because
statement.
 Relates two variables (the independent and
dependent).
 Is testable.
Flip Book-Hypothesis
Rationale
Clear, testable statement
Format
Hypothesis: If ____________________
(Independent Variable)
___________, then the ______________ _______
(changes)
(Dependent Variable)
(Changes)
because ________________________.
(based on background info)
**** Do NOT use I, we, me, etc.****
My Responsibility
Form an educated guess
based on background
information and prior
knowledge
Example
Hypothesis: If the amount of sunlight is
increased then the height of the plant will
increase because it has more energy to drive the
process of photosynthesis.
Identify Variables

Independent Variable- the factor that you
manipulate, the factor that you change or
monitor in an experiment. Cause
 X-axis
 Answers the question: What do I change?

Dependent Variable- the factor that changes in
response to the independent variable, the
results, the outcome that is being measured or
observed in an experiment. Effect
 Y-axis
 Answers the questions: What do I
measure/observe?
Variables Continued

Constant Variables- During the experiment to
only test one variable OR the independent
variable scientists use CONSTANTS.
 Constants are factors in an experiment that stay the
same throughout the whole experiment.
 Answers the question: What do I keep the same?
Flip Book- Variables
Rationale
Necessary to have a controlled
experiment
My Responsibility
• Identify one independent variable
• What do I change?
• Identify one dependent variable (the
results)
• What do I measure/observe?
• Identify at least two constants
• These MUST stay the same
through ALL trials
Format
Variables:
Independent: ONE
Dependent: ONE
Constants: At least two
Example
Variables:
Independent: Amount of
sunlight
Dependent: Height of plant
(cm)
Constants:
Amount of water given
Type of soil
Size of pot
Film Canister- Hypothesis

Hypothesis: If the amount of water is
increased then the reaction time of
the lid popping off will decrease
because there is less room in the
canister for the pressure to build
therefore popping off earlier.
Film Canister Lab- Variables
Variables:
Independent: Amount of Water
Dependent: Reaction time(seconds)
Constants:
Brand of effervescent tablet.
Amount of effervescent tablet
Materials
A detailed list of all the equipment and
materials needed to conduct the
experiment.
 You must be specific and methodical
so that someone could exactly
duplicate your experiment.
 Use brand names and/or numbers for
every single item on your list
 Bullet the list with the details listed at
the end of each item
Flip Book- Materials
Rationale
Format
Lists all equipment and materials Materials:
used during an investigation
• Needs to be bullet points
• Brand names
• Quantities
My Responsibility
Gather listed equipment and
materials
OR
Identify and gather the
equipment and materials
Example
Materials:
• (1) Beaker: plastic, 600
mL, Nalgene
• Miracle Grow Potting Soil,
600 grams
• Sam’s Farm Bean Seeds,
100 seeds total
• 3 L of tap water
Film Canister- Materials
Materials:
• 2 Alka-Seltzer tablets
• 1 film canister with cap
• 1 graduated cylinder
• 1 thermometer
• 1 timer/stopwatch
• 100 mL of tap water
• Paper towels to clean up mess
Procedure
Write a detailed and precise procedure that
includes the correct sequence of steps to be
taken
The procedure should be specific and
methodical so that another experimenter
could duplicate the experiment without
having to ask you ANY questions!
 Write for one level of the independent
variable and add repetitions for repeated
trials
 Written in step by step form using
numbers
Flip Book- Procedure
Rationale
Format
Logical, detailed steps
Procedure:
written so that another
1. Listed in numerical steps
scientist could duplicate
2. Include multiple trials when applicable
the exact lab
3. Can use “repeat” for multiple trials
My Responsibility
Example
Follow the detailed steps Procedure:
1. Get the materials
exactly
2. Pour 100 kg of potting soil into the
AND/OR
6” pot.
Write the detailed steps
3. Place 10 seeds in the center of the
to be followed
pot.
4. Pour another 100 kg of soil on top
of the seeds.
5. Lightly pack down the soil.
6. Repeat steps 2-5 for the other 10
pots
Film Canister- Procedure
Procedure:
1. Break the tablet in half.
2. Measure 10 mL of tap water
3. Measure the temperature of the water.
4. Pour the 10 mL of tap water into the film
canister.
5. Add one half of the tablet to a film canister.
6. Quickly cap the canister and turn upside down
so the cap is resting on the table.
7. Measure the time it takes to pop the top and
record in the data table.
8. Repeat steps 2-7 for one more trial.
9. Repeat steps 2-8 for 20 mL of water.
Data
Excellent way to organize and show trends in
data.
 Many types of graphs to show data.
 Data Table
 Drawings
 Graphs
○ Bar graph- most common, best when I.V. is not
numerical.
○ Line graph-mostly used when you have numerical
I.V. and D.V.
Flip Book-Data
Rationale
Used to organize the results of an
investigation and used to identify
trends and patterns in an
investigation
Format
Data Table:
Graph:
My Responsibility
Accurately collect and record data in
an organized format (chart, table,
graph, drawing, etc.)
Example
Film Canister- Data

Make a Data Table in your lab
IV- Amount DV- Time in seconds
of WaterTrial 1
Trial 2
mL
Constants
Mean
Amount of
tablet
Temp of
water
10 mL
20 mL

Make a graph once you collected your data
Conclusion


Paragraph or several paragraphs stating whether
the data supported the hypothesis or not, the major
findings including evidence from your data, include
trends present in data, what happened that was
unexpected (if any) and possible reasons why.
Also include any recommendations that would
improved your experiment
 Remember that science is done by humans so what are
some human errors? Things you might not have been
aware of before the experiment and know now that you
would do differently.

Could also include possible things for further study
Flip Book- Conclusion
Rationale
Analyze and summarize
the investigation to
determine if the
hypothesis has been
supported
My Responsibility
Write a paragraph or
several paragraphs stating
the major findings of the
investigation and whether
or not the hypothesis has
been supported
Format
Conclusion:
THIS IS IN PARAGRAPH FORM- Use
transition words between sentences
• Begin by restating the purpose.
• Restate the hypothesis and include whether or
not the hypothesis was supported or
unsupported.
• State and interpret the major findings from the
investigation. This will act as the evidence to
justify your claim (hypothesis was supported
or unsupported).
• Include any recommendations that may have
improved your investigation, and/or any errors
that might have occurred that would impact the
results of the investigation.
• End with an application statement (real world
connection or in class connection).
Example
SEE FILM CANISTER LAB
Film Canister- Conclusion
Report out or Redo experiment
Scientist review their investigation. They
either
 make their studies known to the
scientific community.
 It is subject to peer review.
OR
 Make revisions to experiment
 Retest their revised investigation