Download Metrics and Significant Figures Activity

Metrics and Significant
Figures Activity
First we will examine the metric system
then use significant figures to make
measurements and do calculations
The Metric System
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Mass is measured in
grams
Length or distance is
measured in meters
Volume or capacity is
measured in liters
Time is measured in
seconds
Energy is measured in
Joules
Temperature is measured
in Kelvin (not degrees)
Quantity is measured in
moles
The Liter (L)
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A liter is slightly
smaller than a quart
A gallon is roughly 4
times larger than a
liter
The Meter (m)
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The meter is slightly
longer than a yard
1 inch = 2.54 cm (this
is the only English to
metric conversion you
must know
Gram (g)
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A gram’s mass is
approximately the
mass of 2 paperclips.
Many medicines are
massed by their
active ingredients in
grams or parts of a
gram.
English to Metric Comparisons
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1.
2.
3.
4.
5.
6.
7.
Which is larger?
Meter or yard
Mile or Kilometer
Gallon or liter
Pound or gram
Quart or liter
Centimeter or inch
Gram or ounce
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1.
2.
3.
4.
5.
6.
What is the
abbreviation for
each unit?
Meter = _____
Gram = _____
Liter = ______
Second = ______
Joule = _______
Mole = _______
Metric Abbreviations
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The BASE units for the metric system are gram,
liter, meter, second, Kelvin, Joule and mole.
There are larger and smaller portions of each
of these
Their abbreviations come in front of the unit’s
abbreviation (ex. Centimeter = cm)
Larger and Smaller Prefixes
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Larger
1 billion = GIGA (G)
1 million = MEGA (M)
1,000 = kilo (k)
100 = hecto (h)
10 = deca (D, dk, or
da)
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Smaller
1trillion = pico (p)
1 billion = nano (n)
1 million = micro (m)
1,000 = milli (m)
100 = centi (c )
10 = deci (d)
Match the abbreviation with the
name
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Cm = ________
mg = ________
ML = ________
Gg = ________
ms = ________
km = _______
mL = _______
kJ = ________
mm= _______
Dg = _______
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Centimeter
Milligram
Megaliter
Gigagram
Microsecond
Kilometer
Milliliter
Kilojoule
Millimeter
decagram
Conversions
Kilo
Hecto Deca
UNIT
1.0
Deci
Centi
Milli
100
3.09
2594
73.60
0.000765
0.763
730638
84300
Conversions
G
M k
h
D
unit
d
c
m m
1.0
3.9
1x10-9
7x 106
403
7.62
27
848
626
n
p
Significant Figures
• Read the correct
number of significant
figures
Measure the following using
significant figures
Use Sig. Figs to find this
measurement
Use the correct number of sig. figs
in this measurement
What digit would be estimated
in using this ruler?
A.
B.
C.
D.
E.
Ones
Tenths
Hundredths
Thousandths
Tens
What decimal place is estimated
when using this ruler?
A. Ones
B. Tenths
C. Hundredths
D. Thousandths
E. Tens
Measure the width of the
rectangle using the correct
number of sig figs.
A. 3. 75 cm
B. 3.6 cm
C. 2. 6 cm
D. 3.60 cm
E. 4.25 cm
Measure the length of the
rectangle using the correct
number of sig figs.
A. 12.55 cm
B. 12. 5 cm
C. 12.0 cm
E. 13.50 cm
D. 13. 5 cm
How many sig figs should be in the
correct measurement of the length
of this rectangle?
A. 2 sig figs
fig
B. 3 sig figs
C. 4 sig figs
D. 5 sig figs
E. 1 sig
The width of this rectangle is 0.90 cm.
How many significant figures are in this
measurement?
A. 3 sig figs
B. 2 sig figs
C. 1 sig fig
D. infinite sig figs
E. none of the above
Multiplication and Division with Sig
Figs
• The least number of sig figs in the input is
equal to the number of sig figs in the
answer (output).
• Remember all conversion factors and
counted numbers have INFINITE sig figs!
• Example: 8.00 g x 4.0 cm3/g = ?
• 8.0 cm3
Addition and Subtraction with Sig
Figs
• The least number of decimal places in the
input is the same number of decimal
places in the output (answer).
• 12.573 m + 3847.9 m - 378 m = ?
• 3482.473 (unrounded)
• 3482 rounded to the correct number of
decimal places
Calculations with Sig Figs
1. A rectangle has a width of 5.0 cm and a
length of 8.40 cm. What is the area of
this rectangle in cm2? ___________
2. A rectangular prism has the following
measurements: length 8.54 cm, width
7.80cm, and height 10.00 cm. What is
the volume in cm3? ______________