Transcript Mysterious M&M’s: Scientific Method

Science Investigation
September 2,
2011
Ms. Smith
Mrs. Malone
DO NOW:
1. Pick up your handouts.
2. Put the “M&M Reading” homework on the
corner of your desk.
3. Complete the “Lab Safety Matching Cards”
handout.
:
Well-Defined Questions
Ask about objects, organisms, and events in
the natural world.
Can be answered through investigations that
involve experiments, observations, or surveys.
Are answered by collecting and analyzing
evidence that is measurable.
Relate to scientific ideas rather than personal
preference or moral values.
Do not relate to the supernatural or to nonmeasurable phenomena.
How does a paper airplane fly?
Not welldefined.
Does the shape of the wing affect how far
a paper airplane will fly?
Well-defined!
Is rock music better than hip-hop music?
Not welldefined.
Does rock music make more money than
hip-hop music?
Well-defined!
What temperature of water will dissolve
M&Ms faster?
Well-defined!
Which M&M tastes better: red or yellow?
Not welldefined.
Hypothesis
A hypothesis is an educated guess about how
things work.
Create a hypothesis for the following
scientific question.
Question: Does vinegar cause M&M colors
to dissolve faster than water?
Hypothesis
Question:
“Do some M&M colors dissolve faster in water than others?”
Write your hypothesis behind the “Hypothesis” tab
in your foldable.
I predict…
Hypothesis
• IF the M&M has a darker color, THEN it will
dissolve faster.
• IF the M&M has a lighter color, THEN it will
dissolve faster.
Materials
Behind the “Materials” tab in your foldable, list all of the
materials that you will be using in the M&M Investigation lab.
Materials:
• White paper
• Different colored M&Ms
• Water
• Pipette
• Petri dish
• Beaker
• Marker
• Timer
• Paper towels
Variables
• These changing quantities are called
VARIABLES.
• An experiment has 3 kinds of variables:
independent (manipulated), dependent
(responding) and controlled (constants)
Independent Variable
• Variable that is purposely changed or manipulated
• a fair test has only one independent variable.
Example:
Does the amount of fertilizer affect plant growth?
The amount of fertilizer is the independent variable
because the scientist has control over how much
fertilizer is used in the experiment.
Independent Variable
Suppose that you wonder whether you can run a marathon
faster when
you eat pasta the night before or when you drink coffee the
morning of the race.
Your hunch is that loading up on pasta will give you the energy
to run faster
the next day. The independent variable is the consumption of
pasta, and the dependent variable is how fast you run the
race.
Now, if you eat several plates of spaghetti the night before you
race, but then get up the next morning and drink two cups of
coffee before you head to the start line, your experiment is
useless.
Independent Variable
What is the
independent variable
in your M&M investigation?
Independent Variable
Independent Variable:
M&M Color
Why is M&M color the independent variable?
Dependent Variable
• what is measured in the experiment
Example:
Does the amount of fertilizer affect plant growth?
Dependent Variable
What is the
dependent variable
in your M&M investigation?
Dependent Variable
Answer: How fast the
M&M colors dissolve.
Constants
• The variables that are not changed are called controlled variables.
(constants)
Example:
Does the amount of fertilizer affect plant growth?
Independent variable: amount of fertilizer
Dependent variable: plant growth
Controlled variables: same type of plant, same pot size, same
amount of water, same amount of sunlight
Graphs
• A graph is a chart or drawing that shows the
relationship between changing things
• Can you name some common graph types?
• Graphs must include a title and labels on the x
and y axis.
Why will we use a bar graph in our M&M
investigation?
Bar Graph Example
TITLE
Y-Axis
Dependent
Variable
X-Axis Independent Variable
DRY MIX
D = dependent variable
R = responding variable
Y = graph information on the Y-axis (vertical, up and down)
M = manipulated variable
I = independent variable
X = graph information on the X-axis (horizontal, side to side)