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Bio3:
Quiz 1 Study Guide - Fall 2006
Topics:
The quiz will cover lab topics
for Ex. 1 (Process of Scientific Inquiry), A (Tools for Scientific Inquiry) and
2 (pH and Buffers).
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Questions/Hypotheses that can be tested scientifically
- Elements of an experiment (independent/dependent/standardized variables,
control/experimental treatments, sample size/replication)
- Scientific notation
- Length/Mass/Volume/Temperature conversions
- Graphing dependent/independent variables of an experiment and interpreting
graphs correctly
- Characteristics of acids, bases, and buffers
- Interpreting the information in graphs/data tables to determine whether a
solution is a good buffer
Note: The quiz will
contain questions that are similar, but not identical to, the study questions
and the lab review sheet questions. You
will be provided with the following conversion factors on the quiz.
You will be allowed to use a calculator on the quiz.
1km = 1000m
1kg = 1000g
1L = 1000ml
1m = 100cm
1g = 1000mg
1ml = 1000μl
1cm = 10mm
1mg = 1000μg
oC = (oF-32)(5/9)
1mm = 1000μm
1μg = 1000ng
oF = (oCx9/5) + 32
1μm = 1000nm
Study Questions:
1. A scientist is
interested in studying the effects of using different brands of dog food on dog
growth rate. Identify the all
elements of this experiment (IV, DV, StdV, control/exp. treatments, appropriate
sample size)
2. Are the
following hypotheses scientifically testable?
Explain the reason behind your answer.
a) Picasso is a better painter than Monet.
b) Blond women have more fun than brunettes.
c) Eating candy causes children to develop more cavities.
3. Write the
following numbers in decimals:
a) 2.5x104
b) 5.55x10-3
c) 1.45x102
d) 8.9x10-1
4. Write the
following numbers using scientific notation:
a) 34,000
b) 0.123 c) 417
d) 0.0006
5. Complete the
following conversions (you may express your answer using either decimals or
scientific notation):
a) 50cm = ______mm
d) 750g = ______kg
g) 34.6μl = _______ml
b) 35mm = ______m
e) 9800nm = _______mm
h) 90oF = ________ oC
c) 8956 μm = _____cm
f) 20L = _______ml
i) 45oC = ________ oF
6. A scientist
studies the effect of using antibacterial hand soap on eliminating germs.
She finds that using antibacterial hand soap kills the same amount of
germs as regular soap. Graph the
results of this experiment in a concise manner (i.e. decide whether a line graph
or bar graph is more appropriate) and label the axes.
7. You have an
unknown solution at a pH of 6. When
you add a small of acid to this solution, the pH quickly drops.
When you add a small amount of base, it quickly rises.
Is this unknown solution a good buffer?
Explain your answer.
Answers:
1. Independent variable: different brands of dog food
Dependent variable: dog growth rate
Standardized variables: amount of food, the breed/age/environmental factors of
dog studied, # of dogs in each group, etc.
Control treatment: a generic brand of dog food (a “no food” treatment is not
good, since the dog will starve, so it’s better to pick one brand as the
baseline value to compare other brands to)
Experimental treatment: the other dog food brands
Sample size: you would ideally have several dozen dogs in each group to account
for variations among the dogs that you can’t eliminate.
2. a) Picasso is a
better painter than Monet – No, “better” is a subjective term
b) Blond women have more fun than brunettes – No, again, “fun” is a
subjective, and in this case, a vague, unmeasurable term.
c) Eating candy causes children to develop more cavities. – Yes, you can count
the # of cavities that develop, and you can determine the diet habits of the
children by doing a background survey. This
would be more ethical than actually forcing children to eat candy and count the
# of cavities. You would need to
have a large sample size to account for variations among the children though and
standardize as many variables as you can among the different groups.
3. a) 2.5x104
= 25000
b) 5.55x10-3 = 0.00555
c) 1.45x102 = 145
d) 8.9x10-1 = 0.89
4. a) 34,000 =
3.4x104
b) 0.123 = 1.23x10-1
c) 417 = 4.17x102
d) 0.0006 = 6x10-4
5. a) 50cm = 500mm
d) 750g = 0.75kg
g) 34.6μl = 0.0346ml
b) 35mm = 0.035m
e) 9800nm = 9.8x10-3mm
h) 90oF = 32.2 oC
c) 8956 μm = 0.8956cm
f) 20L = 20,000ml
i) 45oC = 113 oF
6.
7. No, the solution is not a good buffer because small
additions of an acid or base cause a change in the pH.
A good buffer would resist changes in pH.
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