Prefix Notes

1
Measurements

• Prefix Notes

2
Significant Figures

• Rules for Counting Significant Figures

• Nonzero integers always count as significant
  figures.
• 1457 has 4 significant figures
• 23.3 has 3 significant figures

3
Metric Prefixes

• Increase or decrease basic unit by 10
• Form new units larger or smaller than the basic
  units
• Indicate a numerical value
• prefix value
• 1 kilometer 1000 meters
• 1 kilogram 1000 grams

4
Prefixes that Increase A Unit

• Prefix Symbol Value
• giga- G 1 000 000 000
• mega- M 1 000 000
• kilo- k 1 000

5
Prefixes that Decrease A Unit

• Prefix Symbol Value
• deci- d 0.1
• centi- c 0.01
• milli- m 0.001
• micro- u 0.000 001
• nano- n 0.000 000 0001

6
Learning check

• Match 1) length 2) mass 3) volume
• _ A. A bag of tomatoes is 4.6 kg.
• __ B. A person is 2.0 m tall.
• __ C. A medication contains 0.50 g Aspirin.
• __ D. A bottle contains 1.5 L of water.

2
1
2
3
7
Learning Check

• Indicate the prefix to use for
• 1. A mass that is 1000 times greater than 1 gram
• 2. A length that is 1/100 of 1 meter?
• 3. A unit of time that is 1/1000 of a second.

2) milli
3) mega
1) kilo
2) centi
1) deci
3) milli
1) nanosecond
2) microsecond
3)millisecond
8
Measurements

• Sig Figs Notes

9
Significant Figures

• Rules for Counting Significant Figures

1. Zeros

1. Leading zeros - never count0.0025 2
   significant figures
2. Captive zeros (zero sandwich) - always count
   1.008 4 significant figures
3. Trailing zeros - count only if the number is
   written with a decimal point 100 1
   significant figure 100. 3 significant
   figures 120.0 4 significant figures

10
Significant Figures

• Rules for Counting Significant Figures

1. Exact numbers - unlimited significant figures

• Not obtained by measurement
• Determined by counting3 apples
• Determined by definition1 in. 2.54 cm

11
Significant Figures

• Rules for Addition and Subtraction

• The number of significant figures in the result
  is the same as in the measurement with the
  smallest number of decimal places.

12
Significant Figures

• Rules for Multiplication and Division

• The number of significant figures in the result
  is the same as in the measurement with the
  smallest number of significant figures.