Go Down the Powers of Ten Scale
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STEM ED/CHM Nanotechnology
Go Down the Power of Ten Scale
Goals of the Activity
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Use a variety of instruments to measure dimensions.
Use scientific notation to describe dimensions in meters, centimeters, and
nanometers.
Compare the size of nanoscale structure with other structures.
Meters, Centimeters and Nanometers
Nanoscale scientists and engineers use a unit called a nanometer when they
describe or measure the dimensions of materials that they design and manufacture. A
nanometer is one billionth of a meter. That means that a distance of one meter is also a
distance of 1 x 109 nanometers. A distance of 10 meters is also a distance of 1 x 10 2
centimeters or 1 x 1010 nanometers.
The data table you will use has four columns. Use the first column to describe a
structure. Measurement or calculations of a dimension are recorded in meters,
centimeters and nanometers in the next three columns.
Use the data below to answer the following 3 questions.
Question 1: What is the length of a smartphone in nanometers?
Question 2: What is the width of an opening in a tennis racquet in centimeters and
nanometers?
Question 3: How many times larger is the width of the classroom door than the width of
the opening in the tennis racquet?
The measurement
Meters
Centimeters
Nanometers
The width of a classroom door
1.20 x 100m
1.20 x 102cm
1.20 x 109nm
The length of a smartphone
1.14 x 10-1m
1.14 x 101cm
The width of an opening in a tennis racquet.
1.06 x 10-2m
Go Down the Powers of Ten Scale
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Activity Stations: There are three stations where you can collect and enter data in
rows of the data table.
 Use a pencil to record data so you can make changes in the rows of the data
table as you collect and record data at the activity stations.
 This activity document also provides information and resources that then can be
used to complete the data table.
The Metric Ruler and Magnifier Station
1. Use a meterstick and a magnifier to measure an object with a dimension larger
than one meter. Record that measurement in the top row of the data table.
2. Use a meterstick and magnifier to measure an object with a dimension less than
one meter Record that measurement in the second row of the data table.
3. Try to use a meterstick and a magnifier to make a measurement that then can be
recorded in the third row of the data table.
Significant Digits
Significant digits include all numerals that you are sure of plus one more estimate
of a numeral that lies somewhere between the smallest divisions on a ruler.
Question 4: What factors limit how many significant digits are included in your
measurements?
Question 5: How far down the Power of Ten Scale can you measure with a magnifier
and a ruler?
The USB Microscope Stations:
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Calibrate the microscope. Directions are at each microscope USB station.
You can use USB microscopes Information to measure smaller dimensions.
Measure Openings in a Coffee Filter
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Calibrate the USB Microscope.
Put a square piece of a coffee filter on the platform of the USB Microscope.
Set the magnification of the USB Microscope to 200x and use the top light.
Gently raise or lower the platform until the structure of the coffee filter comes
into focus.
5. Determine the average screen size of the openings in the coffee filter.
6. Use the magnification power to calculate the actual average size of the openings
in the coffee filter.
7. Record the average size of coffee filter openings in the appropriate row on the
data table.
Question 6: What were some interesting features of the coffee filter?
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Measure the Size of Coffee Grounds
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Put a square of photocopier paper on the platform of the USB microscope.
Use a spoon to put several coffee grounds on the photocopier paper.
Set the magnification of the USB Microscope to 10x and use the top light.
Gently raise or lower the platform to adjust the focus.
Determine the average screen size of the coffee grounds.
Use the magnification power to calculate the average size of coffee grounds.
Record the average size of coffee grounds in the appropriate row on the data
table.
Question 7: How do the sizes of coffee grounds compare with the size of the openings in
the coffee filter?
The Spectrometer Stations:
Spectrometers are instruments use a prism or a diffraction grating to separate
visible light into different colors of light that have different wavelengths. Two models of
spectrometers are available at the Spectrometer Station.
 The blue spectrometer indicates wavelengths of visible light in hundreds of
nanometers. It also indicates the energy of the photons of different colors of
light.
 Aim the narrow slit of the spectroscope toward a fluorescent light on the ceiling.
If you slowly move the spectrometer you can get a visible light spectrum to move
onto a wavelength scale.
 Observe one of the bright lines.
 Record the wavelength of a specific color of visible light in the appropriate row
of the data table.
The following information about different types of filters can be used to
make additional data entries.
Microfiltration: Optical microscopes that are more powerful that the ones you use
today can measure the dimensions of smaller openings in microfilters. Microfilters can
remove bacteria from drinking water.
Question 8: What is the length of bacteria if its length is 0.00000088 meters? Record
that length in an appropriate row of the data table.
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Ultra Filtration: A scanning electron microscope uses a beam of electrons to
illuminate a very small object and creates an image on a monitor. Scanning electron
microscopes can be used to measure the dimensions of openings in ultra filters that can
remove viruses from a water sample.
Question 9: What is the length of a virus if its length is 0.000000027 meters? Record
that length in an appropriate row of the data table.
Nanofiltration: An Atomic Force Microscope (AFM) uses a device similar to a lever to
map objects much smaller than a protein molecule or a virus.
Question 10: An object mapped with an AFM has an opening with a diameter of 2.2
nanometers. What is its length in meters and centimeters? Record that depth in an
appropriate row of the data table.
Reverse Osmosis Filtration: A process called reverse osmosis can be used to filter
harmful ions from a water supply.
Question 11: The diameter of an ion is approximately 6.7 x 10-8 cm. What is its diameter
in meters and nanometers? Record that depth in the last row of the data table.
Question 12: What type of structure would have a dimension smaller than an ion?
Question 13: How much times smaller is the ion in Question 11 than the virus described
in Question 9? Show your calculations.
Question 14: How many times larger is your largest measurement than a structure with
a nanoscale dimension?