Metrics and Significant Metrics and Significant Figures ActivityFigures Activity

First we will examine the metric First we will examine the metric system then use significant figures system then use significant figures

to make measurements and do to make measurements and do calculationscalculations

The Metric System The Metric System Mass is measured in Mass is measured in

grams grams Length or distance is Length or distance is

measured in metersmeasured in meters Volume or capacity is Volume or capacity is

measured in liters measured in liters Time is measured in Time is measured in

seconds seconds Energy is measured in Energy is measured in

JoulesJoules Temperature is measured Temperature is measured

in Kelvin (not degrees)in Kelvin (not degrees) Quantity is measured in Quantity is measured in

molesmoles

The Liter (L) The Liter (L)

A liter is slightly A liter is slightly smaller than a smaller than a quartquart

A gallon is roughly A gallon is roughly 4 times larger than 4 times larger than a litera liter

The Meter (m)The Meter (m)

The meter is The meter is slightly longer than slightly longer than a yarda yard

1 inch = 2.54 cm 1 inch = 2.54 cm (this is the only (this is the only English to metric English to metric conversion you conversion you must knowmust know

Gram (g)Gram (g)

A gram’s mass is A gram’s mass is approximately the approximately the mass of 2 mass of 2 paperclips. paperclips.

Many medicines Many medicines are massed by are massed by their active their active ingredients in ingredients in grams or parts of a grams or parts of a gram. gram.

English to Metric ComparisonsEnglish to Metric Comparisons

Which is larger? Which is larger?

1.1. Meter or yardMeter or yard

2.2. Mile or KilometerMile or Kilometer

3.3. Gallon or literGallon or liter

4.4. Pound or gramPound or gram

5.5. Quart or literQuart or liter

6.6. Centimeter or Centimeter or inchinch

7.7. Gram or ounceGram or ounce

What is the What is the abbreviation for abbreviation for each unit? each unit?

1.1. Meter = _____Meter = _____

2.2. Gram = _____Gram = _____

3.3. Liter = ______Liter = ______

4.4. Second = ______Second = ______

5.5. Joule = _______Joule = _______

6.6. Mole = _______Mole = _______

Metric AbbreviationsMetric Abbreviations

The BASE units for the metric system are The BASE units for the metric system are gram, liter, meter, second, Kelvin, Joule and gram, liter, meter, second, Kelvin, Joule and mole.mole.

There are larger and smaller portions of There are larger and smaller portions of each of theseeach of these

Their abbreviations come in front of the Their abbreviations come in front of the unit’s abbreviation (ex. Centimeter = cm) unit’s abbreviation (ex. Centimeter = cm)

Larger and Smaller PrefixesLarger and Smaller Prefixes

LargerLarger 1 billion = GIGA (G)1 billion = GIGA (G) 1 million = MEGA 1 million = MEGA

(M)(M) 1,000 = kilo (k)1,000 = kilo (k) 100 = hecto (h)100 = hecto (h) 10 = deca (D, dk, 10 = deca (D, dk,

or da)or da)

SmallerSmaller 1trillion = pico (p)1trillion = pico (p) 1 billion = nano (n)1 billion = nano (n) 1 million = micro 1 million = micro

(()) 1,000 = milli (m)1,000 = milli (m) 100 = centi (c )100 = centi (c ) 10 = deci (d)10 = deci (d)

Match the abbreviation with the Match the abbreviation with the namename

1.1. Cm = ________Cm = ________

2.2. mg = ________mg = ________

3.3. ML = ________ML = ________

4.4. Gg = ________Gg = ________

5.5. s = ________s = ________

6.6. km = _______km = _______

7.7. mL = _______mL = _______

8.8. kJ = ________kJ = ________

9.9. mm= _______mm= _______

10.10. Dg = _______Dg = _______

1.1. CentimeterCentimeter

2.2. MilligramMilligram

3.3. MegaliterMegaliter

4.4. GigagramGigagram

5.5. MicrosecondMicrosecond

6.6. KilometerKilometer

7.7. MilliliterMilliliter

8.8. KilojouleKilojoule

9.9. MillimeterMillimeter

10.10. decagramdecagram

ConversionsConversions

KiloKilo HectHectoo

DecaDeca UNITUNIT DeciDeci CentiCenti MilliMilli

1.01.0

100100

3.093.09

25942594

73.673.600

0.000760.0007655

0.760.7633

730638730638

8430843000

ConversionsConversions

GG MM kk hh DD unitunit dd cc mm nn pp1.01.0

3.93.91x10-1x10-99

7x 7x 101066

403403

7.67.622

2727

848848

626626

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. Ones

B. Tenths

C. Hundredths

D. Thousandths

E. Tens

What decimal place is estimated when using this ruler?

A. Ones D. Thousandths

B. Tenths E. Tens

C. Hundredths

Measure the width of the rectangle using the correct

number of sig figs.

A. 3. 75 cm D. 3.60 cm

B. 3.6 cm E. 4.25 cm

C. 2. 6 cm

Measure the length of the rectangle using the correct

number of sig figs.

A. 12.55 cm C. 12.0 cm E. 13.50 cm

B. 12. 5 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 C. 4 sig figs E. 1 sig fig

B. 3 sig figs D. 5 sig figs

The width of this rectangle is 0.90 cm. How many significant figures are in this

measurement?

A. 3 sig figs D. infinite sig figs

B. 2 sig figs E. none of the above

C. 1 sig fig

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? ______________