Module

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Module
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Module 1
What is Science? Scientia knowledge Process
that uses observations and investigations to gain
information about events in nature.
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Module 1
What is the scientific method? organized set of
investigating procedures
State the problem Gather information Form a
hypothesis Test hypothesis Analyze data Draw
conclusions
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This could be a question about an observed
problem or curiosity.
It is never wrong to have a wrong hypothesis.
Your conclusions should simply either support or
not support you hypothesis.
Researching aspects of the problem to understand
it.
A possible explanation for a problem this may
be right or it may be wrong.
Develop an experiment to try to prove or disprove
your hypothesis.
The data will either support or not support your
hypothesis. The data speaks for itself and should
be viewed without prejudice
The conclusion should refer to the data as either
the validation of or the contradiction to your
hypothesis.
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Module 1
Variables are quantities or values which can have
more than one number.
What are variables?
What are the two kinds of variables?
Dependent variables This is the responding
variable the variable that is measured by the
experimenter Independent variable This is the
manipulated variable the variable which is
controlled and changed by the experimenter. The
expression DRY MIX can help you remember and
understand the difference between the two.
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Module 1
D R Y M I X
D
D
R
R
-- Y Axis
Y
-- Dependent Variable
-- Responding Variable (measured)
M
M
-- Manipulated variable (controlled)
I
I
-- X - Axis
X
X
-- Independent Variable (controlled)
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Module 1
What are Constants in an experiment?
A Constant or Constant Variable is a variable
which does not change during the course of the
experiment Example During an experiment which
measures the effect of temperature on plant
growth, the constants might be soil type, plant
type, amount of sunlight, amount of water. All
variables in an experiment should be held
constant except the experimental variables
(dependent and independent)
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Module 1
What is a control in an experiment?
A control is a standard for comparison in an
experiment. For example, in an experiment which
measures the effect of temperature on plant
growth, a plant at room temperature is used to
compare other plants at various temperatures. The
control is the basis for comparison of changes
which take place in the dependent (responding)
variables.
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Module 1
What is an observation? In science an observation
is information collected by the senses all of
the sense not just visual. That information is
often called data. There are two types of data
Qualitative data is information that is
descriptive which does not involve
measurements. Quantitative data are observations
in the form of measurements.
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Module 1
What are models and how are they used in
science? A model is something which represents a
concept which is either very small (the atom),
very large (the solar system), or difficult to
access the real thing (an eyeball). Models help
students to better understand concepts and
relationships.
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Module 1
What is the difference between a hypothesis,
theory, and law? A hypothesis is a possible
answer to science question? Hypotheses may be
right or wrong they give the experimenter a
basis to prove or disprove. A theory is an
explanation of a thing or event based on
knowledge gained from experiments or
investigations.
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Module 1
A scientific law is a rule of nature which seems
to be always true. The law of gravity
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Module 1
What is a measurement standard? A measurement
standard is an agreed-upon exact quantity for
measuring. What is a unit? A unit is
measurement quantity used to describe a
measurement value. UNITS ARE IMPORTANT. A
measurement contains a number and a unit. The
number is the adjective and the unit is the noun.
The number describes (modifies) the unit.
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Module 1
Example This morning I awakened early and ran
five before breakfast. Five what ? 5 miles, 5
minutes, 5 meters, 5 secs, 5 feet. Numbers in a
measurement are MEANINGLESS without units.
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Module 1
The Metric System Base units SI Prefixes
And all of these prefixes
You must know these
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Length
Module 1
SI unit of length is the meter
Definition - distance light travels in a vacuum
in 1/299,792,458 of a second.
A meter is about the distance from the floor to a
doorknob. Measurements smaller than a meter are
usually centimeters. Longer distances are
usually in kilometers.
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Mass - amount of matter in an object
Module 1
SI Unit is the kilogram.
Standard is a palladium-iridium cylinder kept in
France.
One liter of water has a mass of 1 kilogram.
A paper clip has a mass of about a gram. Smaller
mass quantities are measured in milligrams.
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Time - Second
Module 1
1/60th of a minute
Also defined by the number of vibrations of a
Cesium-133 atom.
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Units of Temperature Temperature simply
measures how hot or cold something is In science
temperature is measured in degrees Celsius
(oC). In daily life temperature is measured in
degrees Fahrenheit (oF). (For example, The high
temperature for today is 82 oF or body
temperature is 98.6 oF) Converting between oF and
oC oC 5/9(oF 32) oF 9/5oC 32
Practice 98.6oF ___ oC oC 5/9 (98.6 32)
37oC
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Temperature conversions practice Convert -12oC
to oF oF 9/5 (-12) 32 10.4 oF Kelvin
Temperature Scale A third temperature scale
used to perform temperature calculations. oC and
oF temperatures do not show proportional
relationships and are rarely used in calculations
because they have zero and negative values.
Kelvin is related to oC in the following way K
oC 273
Practice ?200oC ____K
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Derived Units - units which get their meaning
from other units
Volume - amount of space an object occupies.
Volume is derived from units of length. 1 Liter
is equal to 1 dm3 or 1000 cm3
10 cm
10 cm
1 dm 10 cm
10 cm
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Density - A Derived Unit
Module 1
Density is derived from units of mass and volume
and refers to the overall lightness or
heaviness of a substance.
m v
mass volume
or d
Density
The density of water is 1.00 grams/cm3 . Objects
with a density less than 1 gram/cm3 will
generally float in water and objects with a
density greater than 1.00 grams/cm3 will
generally sink in water.
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Module 1
Units of Measurement in Calculations. Conversion
Factors
Definition - a problem-solving method based upon
treating units in calculations as if they are
algebraic factors.

• Unit Conversions (or conversion factors) are
• a fraction with units
• equal to a value of ONE

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Module 1
Using a Conversion Factor
How many hours are in 1 Week?
hours
What is your unknown?
What is your known?
1 Week
Find numerical relationships which link your
known to your unknown.
1 wk 7 days
1 day 24 hours
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Module 1
Solving Problems
Start with your known
7 Days 1 Week
24 hours 1 day
------
1 Week
X
X
168 hrs
-------
-------
----
Multiply by conversion factors which cancel the
unit
Cancel the units, leaving the units to the
unknown.
Solve the problem.
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What are Significant Figures?
Module 1
Definition - The number of digits in a
measurement known to be exact, plus the last
digit which is estimated. This will show you why
5 X 5 ? 25
Significant Figures relates directly to accuracy.
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Significant Figures Rules

• Nonzero Digits are significant. 677.3 mm 4SF
• All zeros between nonzero digits are significant.
  7.003 grams 4SF
• Zeros which begin a number containing a decimal
  are NOT significant. 0.00045 mL 2SF
• All zeros which end a number containing a decimal
  point are significant. 1.00 meters 3SF
• Zeros ending a number with no decimal point are
  questionable and are assumed insignificant.
  40,000 people 1SF

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Practice Problems
Module 1
7.70 grams
3sf
0.0050 meters
2sf
612,000 microbes
3sf
5.000 km
4sf
50070 mm
4sf
6.020 X 1012 atoms
4sf
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Calculations involving Sig Figs
Module 1
Addition and Subtraction
When adding or subtracting measurements, the
final answer may have no more digits to the right
of the decimal point than the measurement with
the fewer number of digits to the right of the
decimal point.
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Addition and Subtraction Examples
4.12 grams 4.2 grams
2 digits to the right of decimal
1 digit to the right of decimal
/
8.32 grams
Answer limited to 1 digit to the right of the
decimal
8.3 grams
Correct answer
53.787 meters - 7.32 meters
3 digits to the right of decimal
2 digits to the right of decimal
/
46.467 meters
Answer limited to two digits to the right of the
decimal
Since the number rounded off is 5 or greater the
last digit is rounded up one.
Answer 46.47 meters
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Multiplication and Division
The answer to a multiplication or division
problem may have no more significant figures than
the measurement with the fewer (or fewest) number
of significant figures.
CALCULATOR GIVES THE WRONG ANSWER!!
/
/
33.67 mm x 6.26 mm 210.7742 mm 2
/
/
Calculator gives answer with 7 sf
3sf
4sf
Round answer off to three sf.
Correct answer 211 mm2
Remember that an answer may be no more accurate
than the least accurate measurement.
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Calculations involving Significant Figures
5 m X 5m 25 m2
/ NOT
Major Concept An answer to a calculation may be
no more accurate that the least accurate
measurement
5 m X 5m 25 m2
1sf
1sf
2sf
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Accurate Measurements are important
5.0 m X 5.0 m 25 m2
Honest, accurate calculation
More accurate measurements
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Density Calculations What is the density of a
metal with a mass of 43.6 grams and a volume of
3.77 cm3?
3 sig figs
Density
3 sig figs
Calculator answer is 11.56498674 g/cm3
WRONG ANSWER
Answer should only have 3 sig figs
Correct rounded answer 11.6 g/cm3
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Scientific Notation

• One number with two parts, used for three
  reasons
• To represent very large numbers
• To represent very small numbers
• To clarify accuracy

First part of the number is the coefficient
6.023 X
1023
One number with two parts
The second part is the base ten exponent.
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Module 1
A graph is a visual display of data or
information. In science data is collected and
displayed in a manner to be easily understood and
interpreted.
This is a bar graph
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Module 1
This is a pie graph or circle graph. It is used
to show parts of a whole. The sum of all parts is
equal to 100
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Module 1
This is a line graph. It shows relationships
between two variables. In this example the
variables are temperature and time. Temperature
is the dependent variable and time is the
independent variable.
time (min)
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Practice Questions

• The next series of slides will give you some
  practice questions to prepare you for the end of
  course test.
• Answers are provided after each question slide.
  Make sure you think about these carefully.
• Please email with questions regarding any
  questions you do not understand.

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• A regional manager is concerned about the number
  of employee accidents occurring at his ten
  service centers. She makes a hypothesis that
  safety advertising will reduce accidents. She
  decides to test the hypothesis in her service
  centers. Each service center will use different
  number of safety posters to see if the number of
  accidents will reduce. Each service center
  manager will keep a record of the employee
  accidents reported.
• How is safety advertising measured in this study?
• number of employee accidents reported to the
  service center manager
• number of service centers involved
• number of safety posters in each service center
• number of accidents in the service center

41

• A regional manager is concerned about the number
  of employee accidents occurring at his ten
  service centers. She makes a hypothesis that
  safety advertising will reduce accidents. She
  decides to test the hypothesis in her service
  centers. Each service center will use different
  number of safety posters to see if the number of
  accidents will reduce. Each service center
  manager will keep a record of the employee
  accidents reported.
• How is safety advertising measured in this study?
• number of employee accidents reported to the
  service center manager
• number of service centers involved
• number of safety posters in each service center
• number of accidents in the service center

42
A regional manager is concerned about the number
of employee accidents occurring at his ten
service centers. She makes a hypothesis that
safety advertising will reduce accidents. She
decides to test the hypothesis in her service
centers. Each service center will use different
number of safety posters to see if the number of
accidents will reduce. Each service center
manager will keep a record of the employee
accidents reported. How are the employee
accidents measured in this study? a. number of
employee accidents reported to the service center
manager b. number of service centers
involved c. number of safety posters in each
service center d. number of accidents in each
service center
43
A regional manager is concerned about the number
of employee accidents occurring at his ten
service centers. She makes a hypothesis that
safety advertising will reduce accidents. She
decides to test the hypothesis in her service
centers. Each service center will use different
number of safety posters to see if the number of
accidents will reduce. Each service center
manager will keep a record of the employee
accidents reported. How are the employee
accidents measured in this study? a. number of
employee accidents reported to the service center
manager b. number of service centers
involved c. number of safety posters in each
service center d. number of accidents in each
service center
44
Jasmine has been launching water rockets. She can
vary the amount of water in the rocket and the
launching angle of the rocket. She can also
change the weight of the rocket by adding sand to
the nose cone. She is curious about the factors
which affect of the height to which the rocket
will rise. Which of the following is a
hypothesis she could test? a. Rockets using warm
water will rise higher than rockets with cold
water. b. Rockets using five tail fins will rise
higher than rockets with four tail fins. c.
Rockets with a pointed nose cone will rise higher
than rockets with a rounded nose cone. d. Rockets
using more water will rise higher than rockets
with less water.
45
Jasmine has been launching water rockets. She can
vary the amount of water in the rocket and the
launching angle of the rocket. She can also
change the weight of the rocket by adding sand to
the nose cone. She is curious about the factors
which affect of the height to which the rocket
will rise. Which of the following is a
hypothesis she could test? a. Rockets using warm
water will rise higher than rockets with cold
water. b. Rockets using five tail fins will rise
higher than rockets with four tail fins. c.
Rockets with a pointed nose cone will rise higher
than rockets with a rounded nose cone. d. Rockets
using more water will rise higher than rockets
with less water.
46
The monthly heating bill for the Smiths is higher
than all their neighbors. They formulate
hypotheses about factors that affect their
heating bill. Which of the following statements
is NOT a hypothesis which they could test? a. The
greater the number of trees around the house, the
lower the heating bill. b. The fewer number of
doors and windows in a house the lower the
heating bill. c. The larger the house the larger
the heating bill. d. The higher the heating bill,
the more likely a family will seek cheaper
heating methods.
47
The monthly heating bill for the Smiths is higher
than all their neighbors. They formulate
hypotheses about factors that affect their
heating bill. Which of the following statements
is NOT a hypothesis which they could test? a. The
greater the number of trees around the house, the
lower the heating bill. b. The fewer number of
doors and windows in a house the lower the
heating bill. c. The larger the house the larger
the heating bill. d. The higher the heating bill,
the more likely a family will seek cheaper
heating methods.
48
A high school environmental science class studies
factors that might affect pollution in the Reedy
River. They discover that possible factors may
include fertilizers, sewage, and trash from a
landfill. Chemicals in that portion of the river
are not a problem because there are no chemical
plants upstream. Which of the following is a
testable hypothesis? a. The more fertilizer in
the river, the more crops will grow along the
river. b. The more chemical plants there are, the
more chemical pollution that results. c. The more
trash sent to the landfill, the higher the income
of families in the region. d. The more sewage in
the river, the greater the level of pollution.
49
A high school environmental science class studies
factors that might affect pollution in the Reedy
River. They discover that possible factors may
include fertilizers, sewage, and trash from a
landfill. Chemicals in that portion of the river
are not a problem because there are no chemical
plants upstream. Which of the following is a
testable hypothesis? a. The more fertilizer in
the river, the more crops will grow along the
river. b. The more chemical plants there are, the
more chemical pollution that results. c. The more
trash sent to the landfill, the higher the income
of families in the region. d. The more sewage in
the river, the greater the level of pollution.
50
Chickens lay varying numbers of eggs depending
upon several factors. Which of the following is
NOT a suitable testable hypothesis for a study of
these factors? a. Chickens exposed to more hours
of light will lay more eggs. b. Chickens which
produce more eggs seem to lose weight. c.
Chickens in larger cages produce more eggs. d.
Chickens with more protein in their feed produce
more eggs.
51
Chickens lay varying numbers of eggs depending
upon several factors. Which of the following is
NOT a suitable testable hypothesis for a study of
these factors? a. Chickens exposed to more hours
of light will lay more eggs. b. Chickens which
produce more eggs seem to lose weight. c.
Chickens in larger cages produce more eggs. d.
Chickens with more protein in their feed produce
more eggs.
52
Henry was curious to see how light affects the
growth of bread mold. He grew bread mold in
fifteen identical containers containing the same
amount and type of nutrients. Five containers
were kept in total darkness, five were kept in
half darkness and half light, and five were in a
continually lighted condition. At the end of four
days the containers were examined and the growth
of the mold was measured and recorded. Which of
the following is Henrys hypothesis? a. The type
of nutrient used will vary the amount of bread
mold. b. The more light withheld from the bread
mold, the greater the amount of bread mold. c.
The amount of nutrient used will vary the amount
of bread mold. d. The greater the number of
containers, the greater the amount of bread mold.
53
Henry was curious to see how light affects the
growth of bread mold. He grew bread mold in
fifteen identical containers containing the same
amount and type of nutrients. Five containers
were kept in total darkness, five were kept in
half darkness and half light, and five were in a
continually lighted condition. At the end of four
days the containers were examined and the growth
of the mold was measured and recorded. Which of
the following is Henrys hypothesis? a. The type
of nutrient used will vary the amount of bread
mold. b. The more light withheld from the bread
mold, the greater the amount of bread mold. c.
The amount of nutrient used will vary the amount
of bread mold. d. The greater the number of
containers, the greater the amount of bread mold.
54
Henry was curious to see how light affects the
growth of bread mold. He grew bread mold in
fifteen identical containers containing the same
amount and type of nutrients. Five containers
were kept in total darkness, five were kept in
half darkness and half light, and five were in a
continually lighted condition. At the end of four
days the containers were examined and the growth
of the mold was measured and recorded. Which of
the following is the controlled variable? a. the
amount of light exposed to the containers b. the
style of container used c. the temperature of the
bread mold d. the quantity of bread mold
55
Henry was curious to see how light affects the
growth of bread mold. He grew bread mold in
fifteen identical containers containing the same
amount and type of nutrients. Five containers
were kept in total darkness, five were kept in
half darkness and half light, and five were in a
continually lighted condition. At the end of four
days the containers were examined and the growth
of the mold was measured and recorded. Which of
the following is the controlled variable? a. the
amount of light exposed to the containers b. the
style of container used c. the temperature of the
bread mold d. the quantity of bread mold
56
Henry was curious to see how light affects the
growth of bread mold. He grew bread mold in
fifteen identical containers containing the same
amount and type of nutrients. Five containers
were kept in total darkness, five were kept in
half darkness and half light, and five were in a
continually lighted condition. At the end of four
days the containers were examined and the growth
of the mold was measured and recorded. Which of
the following is the dependent or responding
variable? a. the growth of the bread mold b. the
quantity of nutrient in each container c. the
amount of light exposed to each of the
containers d. the number of containers used.
57
Henry was curious to see how light affects the
growth of bread mold. He grew bread mold in
fifteen identical containers containing the same
amount and type of nutrients. Five containers
were kept in total darkness, five were kept in
half darkness and half light, and five were in a
continually lighted condition. At the end of four
days the containers were examined and the growth
of the mold was measured and recorded. Which of
the following is the dependent or responding
variable? a. the growth of the bread mold b. the
quantity of nutrient in each container c. the
amount of light exposed to each of the
containers d. the number of containers used.
58
Henry was curious to see how light affects the
growth of bread mold. He grew bread mold in
fifteen identical containers containing the same
amount and type of nutrients. Five containers
were kept in total darkness, five were kept in
half darkness and half light, and five were in a
continually lighted condition. At the end of four
days the containers were examined and the growth
of the mold was measured and recorded. Which is
the independent or manipulated variable? a. the
amount of light exposed to each of the
containers b. the quantity of nutrient in each
container c. the growth of the bread mold d. the
number of containers for each experimental area
59
Henry was curious to see how light affects the
growth of bread mold. He grew bread mold in
fifteen identical containers containing the same
amount and type of nutrients. Five containers
were kept in total darkness, five were kept in
half darkness and half light, and five were in a
continually lighted condition. At the end of four
days the containers were examined and the growth
of the mold was measured and recorded. Which is
the independent or manipulated variable? a. the
amount of light exposed to each of the
containers b. the quantity of nutrient in each
container c. the growth of the bread mold d. the
number of containers for each experimental area
60
John wanted to find out which type of toothpaste
was best at fighting bacteria. On an agar plate
inoculated with bacteria, he placed 1 cm. of
three different types of toothpaste. What is the
dependent variable in Johns experiment? a. the
amount of bacterial growth b. the different kinds
of toothpaste c. the types of bacteria d. the
amount of toothpaste
61
John wanted to find out which type of toothpaste
was best at fighting bacteria. On an agar plate
inoculated with bacteria, he placed 1 cm. of
three different types of toothpaste. What is the
dependent variable in Johns experiment? a. the
amount of bacterial growth b. the different kinds
of toothpaste c. the types of bacteria d. the
amount of toothpaste
62
Shawn wonders about the things that may affect
the time it takes ice cubes to melt. He
formulates a hypothesis that the shape of the ice
cube affects the time it takes to melt ice cubes.
Shawn believes that the size of the ice cubes
and the temperature of the environment are
factors which may also affect the time it takes
ice cubes to melt. Which of the following would
be the BEST method Shawn could use to test his
hypothesis? a. Use five ice cubes of the same
shape and size. Use five identical containers of
the same temperature. Measure the time it takes
each cube to melt. b. Use five ice cubes of the
same shape and each having a different size. Use
five identical containers of the same
temperature. Measure the time it takes each cube
to melt. c. Use five ice cubes of the same size,
but each having a different shape. Use five
containers of the same temperature. Measure the
time it takes each cube to melt. d. Use five ice
cubes of the same size, but each having a
different shape. Use five containers, each at a
different temperature. Measure the time it takes
each cube to melt.
63
Shawn wonders about the things that may affect
the time it takes ice cubes to melt. He
formulates a hypothesis that the shape of the ice
cube affects the time it takes to melt ice cubes.
Shawn believes that the size of the ice cubes
and the temperature of the environment are
factors which may also affect the time it takes
ice cubes to melt. Which of the following would
be the BEST method Shawn could use to test his
hypothesis? a. Use five ice cubes of the same
shape and size. Use five identical containers of
the same temperature. Measure the time it takes
each cube to melt. b. Use five ice cubes of the
same shape and each having a different size. Use
five identical containers of the same
temperature. Measure the time it takes each cube
to melt. c. Use five ice cubes of the same size,
but each having a different shape. Use five
containers of the same temperature. Measure the
time it takes each cube to melt. d. Use five ice
cubes of the same size, but each having a
different shape. Use five containers, each at a
different temperature. Measure the time it takes
each cube to melt.
64
Thomas wanted to test the hypothesis that the
higher the temperature of the water, the faster
the sugar would dissolve. Which of the following
would BEST test his hypothesis? a. Use four
beakers of water Beaker 1 at 20oC, Beaker 2 at
40oC, Beaker 3 at 60oC, and Beaker 4 at 80oC.
Add one teaspoon of sugar to each beaker and
measure the time it takes to dissolve. b. Use two
beakers of water Beaker 1 at 20oC, Beaker 2 at
30oC. Add one teaspoon of sugar to each beaker
and measure the time it takes to dissolve. c. Use
three beakers of water, all at the same
temperature. Add one teaspoon of sugar to each
beaker. Heat Beaker 1 over low heat. Heat Beaker
2 over high heat. Allow Beaker 3 to remain at
room temperature unheated. Measure the time it
takes for each to dissolve. d. Use four beakers
of water Add 1 teaspoon of sugar to Beaker 1.
Add 2 teaspoons of sugar to Beaker 2. Add 3
teaspoons to Beaker 3. Add 4 teaspoons of sugar
to Beaker 4. Measure the time it takes for each
to dissolve.
65
Thomas wanted to test the hypothesis that the
higher the temperature of the water, the faster
the sugar would dissolve. Which of the following
would BEST test his hypothesis? a. Use four
beakers of water Beaker 1 at 20oC, Beaker 2 at
40oC, Beaker 3 at 60oC, and Beaker 4 at 80oC.
Add one teaspoon of sugar to each beaker and
measure the time it takes to dissolve. b. Use two
beakers of water Beaker 1 at 20oC, Beaker 2 at
30oC. Add one teaspoon of sugar to each beaker
and measure the time it takes to dissolve. c. Use
three beakers of water, all at the same
temperature. Add one teaspoon of sugar to each
beaker. Heat Beaker 1 over low heat. Heat Beaker
2 over high heat. Allow Beaker 3 to remain at
room temperature unheated. Measure the time it
takes for each to dissolve. d. Use four beakers
of water Add 1 teaspoon of sugar to Beaker 1.
Add 2 teaspoons of sugar to Beaker 2. Add 3
teaspoons to Beaker 3. Add 4 teaspoons of sugar
to Beaker 4. Measure the time it takes for each
to dissolve.