Name:_________________________________________ Hr:_____
Unit 1: Scientific Method and Measurement Homework Packet
Part 1: The Scientific Method Applied
In 1928, Sir Alexander Fleming was studying Staphylococcus bacteria growing in culture
dishes. He noticed a mold called Penicillium also growing in some of the dishes. A clear area existed
around the mold. All the bacteria that had grown in this clear area had died. In the culture dishes
without the mold, no clear areas were present.
Fleming hypothesized that the mold must be producing a chemical that killed the bacteria. He decided to
isolate this substance and test it to see if it would kill bacteria. Fleming transferred the mold to a nutrient broth
solution. This solution contained all the materials the mold needed to grow and reproduce. He allowed the mold to
grow. Then he removed the mold from the nutrient broth. Fleming added the nutrient broth in which the mold had
grown to a culture of the bacteria. He observed that the bacteria died. Fleming then added nutrient broth that had not
had mold growing in it to another dish of bacteria. The bacteria in this dish did not die. Fleming concluded that the
mold produced a bacteria-killing substance. He called the substance that killed the bacteria penicillin.
1. Identify the problem Fleming wanted to solve.
2. What was Fleming’s hypothesis?
3. How did Fleming test his hypothesis?
4. What was the independent variable in Fleming’s experiment? Dependent variable?
5. What was used as the control group?
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6. What data did Fleming obtain? (Hint: what new information did Fleming find in his experiments?)
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7. What was his conclusion?
8. Did his data support his hypothesis? (Hint: did his experiment prove or not prove his hypothesis?)
Explain
9. What was discovered as a result of Fleming’s experiment?
10. What is a theory?
11. How do hypotheses, observations, and conclusions relate to theories?
Part 2: Scientific Method with the Simpson’s
Smithers thinks that a
special juice will increase
the productivity of
workers. He creates two
groups of 50 workers
each and assigns each
group the same task (in
this case, they're supposed to staple a set of
papers). Group A is given the special juice to
drink while they work. Group B is not given the
special juice. After an hour, Smithers counts how
many stacks of papers each group has made.
Group A made 1,587 stacks, Group B made
2,113 stacks.
Identify the:
Homer notices that his
shower is covered in a
strange green slime. His
friend Barney tells him
that coconut juice will get
rid of the green slime.
Homer decides to check
this this out by spraying
half of the shower with
coconut juice. He sprays
the other half of the shower with water. After 3
days of "treatment" there is no change in the
appearance of the green slime on either side of
the shower.
6. What was the initial observation?
1. Control Group ________________________________
2. Independent Variable _______________________________
3. Dependent Variable ________________________________
4. What should Smithers' conclusion be?
5. How could this experiment be improved?
Identify the:
7. Control Group ________________________________
8. Independent Variable _______________________________
9. Dependent Variable ________________________________
10. What should Homer's conclusion be?
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Part 3: SpongeBob’s Scientific Method
1) Marshmallow Muscles
Larry was told that a certain muscle cream was the newest best thing on the market and claims
to double a person’s muscle power when used as part of a muscle-building workout. Interested
in this product, he buys the special muscle cream and recruits Patrick and Sponge Bob to help
him with an experiment. Larry develops a special marshmallow weight-lifting program for Patrick
and Sponge Bob. He meets with them once every day for a period of 2 weeks and keeps track
of their results. Before each session Patrick’s arms and back are lathered in the muscle cream,
while Sponge Bob’s arms and back are lathered with the regular lotion.
a. Which person is in the control group?
b. What is the independent variable?
c.
TIME
INITIAL AMOUNT
AFTER ONE WEEK
AFTER TWO WEEKS
PATRICK
18
24
33
SPONGE BOB
5
9
17
What is the dependent variable?
d. What should Larry’s conclusion be?
2) Microwave Miracle
Patrick believes that fish that eat food exposed to microwaves will become smarter and would be
able to swim through a maze faster. He decides to perform an experiment by placing fish food in a
microwave for 20 seconds. He has the fish swim through a maze and records the time it takes for
each one to make it to the end. He feeds the special food to 10 fish and gives regular food to 10
others. After 1 week, he has the fish swim through the maze again and records the times for each.
a. What was Patrick’s hypothesis?
b. Which fish are in the control group?
c.
What is the independent variable?
d. What is the dependent variable?
e. Look at the results in the charts. What should
Patrick’s conclusion be?
3) Super Bubbles
Patrick and Sponge Bob love to blow bubbles! Patrick found some Super
Bubble Soap at Sail-Mart. The ads claim that Super Bubble Soap will produce
bubbles that are twice as big as bubbles made with regular bubble soap. Patrick
and Sponge Bob made up two samples of bubble solution. One sample was
made with 5 oz. of Super Bubble Soap and 5 oz. of water, while the other was
made with the same amount of water and 5 oz. of regular bubble soap. Patrick
and Sponge Bob used their favorite bubble wands to blow 10 different bubbles
and did their best to measure the diameter of each one. The results are shown
in the chart.
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a. What did the Super Bubble ads claim?
b. What is the independent variable?
c.
What is the dependent variable?
d. Look at the results in the chart.
o
Calculate the average diameter for each bubble solution.
Super Bubble = ______ cm Regular Soap = ________ cm
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e.
Based on the results, what should their conclusion be?
Based on experiment setup, do you think the results are reliable? Why or why not?
Part 4: Largest/Smallest Metric Measurements
Directions: Circle the greatest metric measurement in each problem.
1)
500 cm
5000 mm
4m
2)
0.2 L
240 mL
50 cL
3)
3000 mg
250 cg
3 kg
4)
4L
5000 mL
23,000 cL
5)
17 m
17,040,000 cm
17,400,005 mm
6)
2000 cg
25,300 mg
2.5 kg
7)
3400 cg
4.5 kg
7,000,843 mg
8)
23 L
4.3 kL
6,000,320 mL
Directions: Circle the smallest metric measurement in each problem.
1)
500 cm
5000 mm
4m
2)
0.2 L
240 mL
50 cL
3)
3000 mg
250 cg
3 kg
4)
4L
5000 mL
23,000 cL
5)
17 m
17,040,000 cm
17,400,005 mm
6)
2000 cg
25,300 mg
2.5 kg
7)
3400 cg
4.5 kg
7,000,843 mg
8)
23 L
4.3 kL
6,000,320 mL
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Part 5: Metric Mania
Try these conversions, using the line/ladder/step method. If you have a problem with these STOP HERE!
Please come see me to review before moving on.
1) 1000 mg = _______ g
2) 1 L = _______ mL
3) 160 cm = _______ mm
4) 14 km = _______ m
5) 109 g = _______ kg
4) 250 mL = _______ kL
Conversion Challenge
Write the correct abbreviation for each metric unit.
1) Kilogram _____
4) Milliliter _____
7) Kilometer _____
2) Meter _____
5) Millimeter _____
8) Centimeter _____
3) Gram _____
6) Liter _____
9) Milligram _____
Try these conversions, using the line/ladder/step method.
1) 2000 mg = __________ g
6) 5 L = __________ mL
11) 16 cm = __________ mm
2) 104 km = __________ m
7) 198 g = __________ kg
12) 2500 m = __________ km
3) 480 cm = ________ m
8) 75 mL = _________ L
13) 65 g = _________ mg
4) 5.6 kg = ________ g
9) 50 cm = ________ m
14) 6.3 cm = ________ mm
5) 8 mm = ________ cm
10) 5.6 m = ________ cm
15) 120 mg = ________ g
16) 63 cm______ 6 m
17) 5 g _______508 mg
18) 1,500 mL______ 1.5 L
19) 536 cm________ 53.6 dm
20) 43 mg _______ 5 g
21) 3.6 m _______ 36 cm
Compare using <, >, or =
Part 6: Lab Safety Questions (Answer while watching safety video.)
Handling Chemicals Safely
1. When you read the label on a chemical container, what are the three most important pieces of information?
2. How many times should you read this information before you open the container?
3. Is it important to be exact when preparing a chemical reaction? EXPLAIN.
4. What should you do with leftover chemicals after an experiment? What should you do with the products of an
experiment?
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5. How can you draw small volumes of liquids into a pipette safely?
6. Why is it important to read the instructions all the way through before beginning an experiment?
7. When you need to carry chemicals from one place to another in the lab, what size container is the safest to use?
8. If you spill a liquid chemical, what should you do?
9. Should you add acid to water, or water to acid?
Bunsen Burner and Glassware Safety
1. Before hooking a Bunsen burner to the gas line, what should you look for?
2. How quickly should you turn on the gas?
3. When you use a striker, where should you stand?
4. If your flame sputters or goes out, what should you do?
5. If you smell gas in the room, what should you do?
6. Is it safe to heat a sealed container? EXPLAIN.
7. Is it safe to work near heated objects?
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8. Is it safe to use glassware that has cracks or stars? EXPLAIN.
9. How can you safely carry a heated object?
10. Is it safe to heat flammable chemicals (e.g., gasoline) with a Bunsen burner?
Thermometer Safety
1. Thermometers contain either alcohol or mercury to indicate temperature. Which substance (mercury or alcohol)
creates toxic vapors when exposed to air?
2. If you break a mercury thermometer, what is the safe way to clean it up?
3. Before choosing a thermometer for a specific job, what should you know?
Dressing for Safety
1. What types of shoes are appropriate for the lab?
2. Describe the type of clothing you should wear on days when you will be working in the lab.
3. How should you protect your eyes from chemicals and glass shards?
4. Why is it important to remove rings, watches, and contact lenses before working in the lab?
5. How can you protect your hands when working with corrosive chemicals?
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Behavior in the Laboratory
1. Is the laboratory a safe place to eat, drink, or put on makeup? Why or why not?
2. What is the safe way to read a burette that is above your eye level?
3. Where should you keep your personal belongings that you bring to the lab?
Emergency Equipment
1. Name the pieces of safety equipment in your laboratory. Do you know where they are and how to use them?
2. How do you extinguish a small fire in a container? What should you do if you have a larger
fire?
3. How do you put out a clothing fire?
Part 7: Dimensional Analysis
DIRECTIONS: Convert the following problems using dimensional analysis. You must show all work on a
separate piece of paper to receive full credit. Staple your work to the back of this packet. Fill in your final
answers in the blanks below.
1) 2 L =_____________mL
8) 50 yds = ______________m
2) 20 mi = _____________km
9) 50 m = ______________yds
3) 20 km = _____________mi
10) 16 g = ______________oz
4) 500 in = _____________m
11) 3.89 lbs = ______________g
5) 500 m = ______________in
12) 11.9 oz = _______________g
6) 0.5 g = _______________lbs
13) 2.3 lbs = ________________g
7) 0.5 lbs = ______________g
14) 23.8 lbs = _______________kg
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15) 0.050 lbs = ______________kg
27) 11 in = ____________________cm
16) 14 kg = _________________lbs
28) 1 in = _____________________m
17) 135.4 g = ________________lbs
29) 0.70 ft = ___________________m
18) 14.2 oz = _________________lbs
30) 6.7 mi = ___________________km
19) 23.7 g = __________________oz
31) 0.438 m = __________________in
20) 4.3 lbs = __________________oz
32) 18.744 cm = _________________in
21) 3.4 qts = ___________________L
33) 5.67 m = ____________________ft
22) 60 qts = ____________________L
34) 2.80 cm = ___________________ft
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23) 148 cm = _________________mL
35) 4.0 in = _____________________ft
24) 14.3 L = ___________________qts
36) 141 cm = ____________________ft
25) 9.4 ft = ____________________cm
37) 13 km = _____________________mi
26) 6.00 ft = ___________________cm
38) 2180 ft = _____________________mi
Part 8: Graphing Practice
Age of the tree
in years
Average thickness of the
annual rings in cm.
Forest A
Average thickness of the
annual rings in cm.
Forest B
10
2.0
2.2
20
2.2
2.5
30
3.5
3.6
35
3.0
3.8
50
4.5
4.0
60
4.3
4.5
The thickness of the annual rings indicates what type of environmental situation was occurring at the time of its
development. A thin ring usually indicates a rough period of development such as lack of water, forest fires, or a
major insect infestation. On the other hand, a thick ring indicates just the opposite.
A. Make a line graph of the data.
B. What is the dependent variable? __________________________________________
C. What is the independent variable? ________________________________________
D. What was the average thickness of the annual rings of 40 year old trees in Forest A? Forest B?
Forest A :___________________________ Forest B :_____________________________________
E. Based on this data, what can you conclude about Forest A and Forest B?
_______________________________________________________________________________________
_______________________________________________________________________________________
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Title: _________________________________________________________________
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Part 9: Measurements (Use PRECISION for ALL MEASUREMENTS)
Part A
Answer the following 3 questions for each graduated cylinder:
A) What is the size of the interval, in mL, between the finest marks?
B) To what precision can you read the cylinder? (tenths, hundredths, whole number, etc)
C) What is the volume of liquid in the cylinder? (All units are in mL)
1.
2.
3.
A)__________________
A)_________________
A)_________________
B) _________________
B)__________________
B)_________________
C) ________________
C) _________________
C)_________________
4.
5.
6.
A)__________________
A)_________________
A)_________________
B) _________________
B)__________________
B)_________________
C) ________________
C) _________________
C)_________________
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Part B
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Part C
13
Part D
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