THURSDAY, SEPTEMBER 19, 2013
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LT: I can conduct safe lab experiments & use
appropriate measurement tools correctly.
EW: List the base SI units for length, volume and
mass.
Today:
Metric System/Measurement Review Notes
 Finish Procedure

The Metric System &
Measurement
BASIC UNITS

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Mass:
Length:
Volume:
Temperature
gram (g)
meter (m)
Liter (L) or (l)
Celsius (°C)
or Kelvin (K)
CONVERTING

Base 10 system
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Converting bigger to smaller unit
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
move decimal to the right; the equivalence is
bigger.
ex. meters to centimeters
Converting smaller to bigger unit



Move decimal right – X 10
move decimal left - ÷ 10
move decimal to the left; the equivalence is
smaller.
ex. meters to kilometers
Let’s see how this works!
THE CONVERSION LADDER
Kilo-
1000
units
Hecto100
units
To convert to a smaller
unit (going down the
ladder) move the decimal
to the right, or multiply
Deka10
units
To convert to a bigger
unit (going up the ladder)
move the decimal to the
left, or divide
Basic
Unit
deci0.1
units
centi0.01
units
milli0.001
units
LET’S PRACTICE
Use the ladder method to find these
equivalences:
 1)
2 g = __________mg
 Remember, count the number of steps you
need to take on the ladder. If you are
going up the ladder, move the decimal
that many places to the left. If you are
going down the ladder, move the decimal
that many places to the right.

LET’S TRY A FEW MORE…
2)
 3)

1000 ml = ____________ Kl
500 m = _____________cm
Now for a few challenging ones
 4)
325.2 cg = __________Dg
 5)
0.9683 HL = _________dL

CONVERTING BETWEEN SYSTEMS
Must know conversion factor (ratio showing how
many units of one system are in 1 unit in the
other system).
 Handy conversion factors:
 2.54 cm/1 in
 1.609 km/1 mi
 30.48 cm/1 ft
 39.37 in/1 m
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EXAMPLE & PRACTICE!
EX. If 2.2 lbs equals 1 kg, how many kgs is 525 lbs?
Set up dimensional analysis:
1. Write given measurement & X
2. Set up conversion factor – put unit you are
converting from in the denominator.
3. Put unit you are converting to in numerator.
4. Put 1 next to larger unit and how many equals
one next to smaller unit.
525 lbs X 1 kg
2.2 lbs
5. Cancel units
6. Do the math!
Try this!
Bode’s beautiful tail is 2.7 ft. long. How many
centimeters is Bode’s tail? Remember there are 30.48
cm in 1 ft.
SIGNIFICANT DIGITS
Meaningful digits in a measured quantity.
 Last digit may be uncertain (an estimate), but it
is still significant.
 When doing calculations with measurements
with different amounts of significant digits, your
answer can only have as many digits as the least
number you are working with. If your answer has
more, you must round your answer.

EXAMPLES
How many significant digits in 5.24?
 If I divide 5.24 by 3.8, how many significant
digits can I have in my answer?
 My calculator gave me the answer 1.378947368.
What number should I report?
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USING MEASUREMENT EQUIPMENT
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Distance – ruler or meter stick

Volume – graduated cylinder
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Mass – triple beam balance
digital balance
Temperature – thermometer
digital probe
Tutorial
TUESDAY, SEPTEMBER 17, 2013
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LT: I can conduct safe lab experiments and use
appropriate measurement tools correctly.
EW:
1. 342.6 Kg = ? cg?
2. 3.4 in. = ? cm? (2.54 cm = 1 in.)
Today:
Measurement Lab
WEDNESDAY, SEPTEMBER 18, 2013
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
LT: I can conduct safe lab experiments and use
appropriate measurement tools correctly.
EW:
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
If the triple beam balance can mass to the 10th of a
gram, how many decimal places should be in your
mass calculation?
Today:
Homework Quiz
 Measurement Lab – You will be assessed today on
participation, thoroughness and neatness of your lab
work - +4 points possible

CH. 1 HOMEWORK QUIZ
1. The English System of measurement is one system of
measurement. What is the other system of measurement?
2. What is the prefix that indicates 1000 items or base units
(it means 1000)?
3. What is an independent variable?
4. What is the responding (dependent) variable?
5. Convert 650 millimeters (mm) to meters (m)
6. Draw a picture of an xy graph. (label the x AND y axis)
MEASUREMENT LAB
First lab in Composition Lab Note Book!
 First page – Table of Contents
 Third page – Title: Measurement Lab
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Directions:
You will visit 6 stations. Provide a clear title in your
book for the work you do at each station!
 Follow the directions posted at each station, doing
the written work in your Comp Book.
 Station 7, if time allows.
 Finish by answering Focus Questions
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MEASURING FOCUS QUESTIONS
When measuring, for which digit do scientists
expect uncertainty? Explain why it is still
significant and should be reported.
 Why would you zero a balance before each use?
 Why would you zero the weighing dish before
placing the substance in it?
 When you used 2 different technologies to
measure mass or temperature, did the
measurements match exactly? Why might they
have been different?
 List and explain 3 safety rules you followed in
this lab.
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