Measurement Homework Packet

Name: ____________________________ Class Period: _______________________

Name:

Metric System Equalities

Write an equality for the following metric unit pairs:

1, mm and cm

2, kL and L

3, kg and g

4, g and mg

5. cm and m

6, mg and g

7. L and cL

8. cg and mg

9. km and m

10. g and kg

11. mLand cL

12, ml and L

13. mm and m

14. m and pm

15. ng and g

16. hL and L

i7. Gg and I(g

18. ng and cg

19. pg and cg

20. Mg and g

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Nÿme

MeasurementACCURACY &

Idea 1 : Measurements (3,25 cm) are different than other numbers (3.14159265),

[] Measurements represent an action by someone with some measuring instrument,

Measurements have built-in uncertainty; no measurement is exact.

. Measurements have units,

Idea 2: The uncertainty in a measurement needs to be communicated.

Definitions:

accuracy - how close a measurement is to

precision - how close a measurement is to

PRECIISmON

Precision versus Accuracy.'

Look at each target below and decide whether the situation is accurate, precise, both, or neither:

(Note: it is "accepted" that the bull's eye is the place evelyone aims for.)

Accurate?: Yes / No Accurate?: Yes / No Accurate?: Yes / No

Precise?: Yes / No Precise?: Yes / No Precise?: Yes / No

Precision Problems:

Several lab groups measure the density of aluminum. Here is their data:!

Team 1 Team 2 [ Team 3 Team 4 Team 5 Team 6

2.65 g!cm! . 2,75 g!em3! 2,80g!cm3 _ÿ_[ 2.60ÿ/cm3 2.65 g!cm3

1, What is the average density? g/era3

2. The actual density of aluminum is 2.7 g/era3, Is the average density (accurate or precise)?

3, Here is more data. Is this more precise, less precise, or the same precision as the above data?

Team 1 Team 2 Team 3 Team 4 Team 5 Team 6

2,60 g/cm3 2.70 g/cm3 2.80 g/em3 2.75 g/cm3 2.65 g/cm3 2.62 g/cm3

Team 7

2,68 g!cm3

Team 7

2,78 g/era3

CALCULATE PERCENT ERROR FOR THE FOLLOWING VALUES:1. Laura determined the melting point of a substance to be 24,5 C, Find the percent error of her measurement if

the actual melting point is 31.2 C,

2, The molar mass of butane is 58.14 g/mol, Using his lab data, Elliott calculated the molar mass of butane as44.2 g/tool. Find the percent error of his measurement.

2

Name Per,

Scientific Notation Worksheef.When using scientific notation:

1. a, Should numbers greater than or equal to 10 be expressed with positive ornegative powers of 10? (circle one)

b. Should numbers less than 1 be expressed with positive or negativepowers of 10? (circle one)

2, What about a number that falls between 1 and 10?

Express the following in scientific notation:

EX. 7

3, 985,0004. O.OOOO875. 8.8456, 0.02327. 0.758. 7,456,9219, 65,51010. 2001 t, 0,000212. 110013. 455O,7!4, 4

Express the following in regular notation:

15. 8.99 x 10-216. 2.95 x t0317. 5,443 x 10418. 1.97x 10-619. 3.4 x 10-120. 6.0002 x 10 321. 2.55 x 10-522. 7.9998 x 10223. 4.008 x !0- 224. 9.999 x 10 725. 4 x 10-3

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WS 1.3 Significant Figures I

6) 3400 g1t) 0,00034 g16) 34.0 g__

21) 3400 g __26) 800 g31) 1,000,000 g__

36) 3,4 x 103 g__

41) 3.0 x103 g

For the followinÿrements indic te how many significant flÿt) 34 g__ 2) 564 Lm 3) 19,3 mm__ 4) 23,45 mg ÿ 5) 101 kin__

7) 5040 L __ 8) 19,000 mm __ÿ 9) 20 mg __ 10) 160 km

t2) 0,564 L__ 13) 0,0019 m 14) 0,5 rag__ 15) 0.12 km

17) 56,40 L 18) 19,00 m__ 19) 20,0 rag,__ 20) 8,200 m

22) 2000 L 23) 14Omm 24) 1900"-0 mg ÿ 25) 6400'kin

27) 800. L ÿ 28) 10,900 mm 29) 10,090 mg ÿ 30) 803 km

32) 1,000,001g o33) 0.05060m 34) 56rag 35) 0m

37) 5.64x108Lÿ 38) 7x lO-Smm 39) 2,4x104g 40) 3,61x102m

42) 5.60 x108 L 43) 2.04 x104 g 44) 6.00xi02 g 45) 2.0 xlOO m

Convert between scientific notation and reqular notation, wilhout chan=qinq the number of siÿ

46) 5700g= ÿ'ÿg 52) 3,6x105m= 360000 m

47) 14,000,000 m = m 53) 3.6 x 10-ÿ m = m

48) 2,000 cm = cm 54) 3.60 x 106 m = m

49) 2,000, cm = cm 55) 6,00 x 101 kg = kg

50) 0.000043 kg = kg 56) 6.00 x 102 kg = kg

51) 0.000230 mg = mg 57) 3.25x 103 L = L

,Round each of the followin,q off to the specified number of slÿ (some have been done for you,,,)

58) Round 78,241 g to,,, 4 sf: 3 sf: 2 sf: ! sf:

59) Round 4.2983 g to,,, 4 sf: __ 3sf: q.ÿ30 2sf: lsf:

60) Round 373,99 g to,.. 4 sf: 3sf: 2sf: ÿÿ lsf:

61) Round 50,001 g to,,. 4 sf: 3 sf: 2 sf: 1 sf:

Arts #1=45 only (IRO): five l's, thirteen 2'e, seventeen 3's, seven 4'e, one 5, one 7, 1 ?

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Scientific Notation/Significant Figures

1. Convert each of the following into scientific notation.

a) 3427 _____________ b) 0.00456 _____________ c) 123,453_____________ d) 172 _____________ e) 0.000984_____________ f) 0.502_____________ g) 3100.0 x 102____________ h) 0.0114 x 104_____________ i) 107.2_____________ j) 0.0000455_____________ k) 2205.2_____________ l) 30.0 x 10-2___________ m) 0.982 x 10-3___________ n) 0.0473_____________ o) 650.502_____________ p) 3.03 x 10-1_____________ q) 20.4 x 105_____________ r) 1.29_____________ s) 0.00565 _____________ t) 1362205.2_____________ u) 450.0 x 103__________ v) 1000 x 10-3_____________

2. Determine the number of significant figures in each of the following:

a) 3427_____________ b) 0.00456_____________ c) 123,453_____________ d) 172_____________ e) 0.000984_____________ f) 0.502_____________ g) 3.1000 x 102___________ h) 1.14 x 104_____________ i) 107.2_____________ j) 0.0000455_____________ k) 2205.2_____________ l) 3.00 x 10-2_____________ m) 9.82 x 10-3___________ n) 0.0473_____________ o) 650.502_____________ p) 3.03 x 10-1_____________ q) 2.04 x 105_____________ r) 1.29_____________ s) 0.00565_____________ t) 1362205.2_____________ u) 4.500 x 103_____________ v) 1.000 x 10-3_____________ w) 546,000 + 10_____________ x) 546,000 + 1000__________

3. Convert each into decimal form.

1.56 x 104_____________ 0.56 x 10-2 _____________ 3.69 x 10-2____________ 0.00259 x 105_____________ 0.000459 x 10-1_____________ 13.69 x 10-2____________ 0.00259 x 103_____________ 0.0209 x 10-3_____________

4. Calculate the following. Give the answer in correct scientific notation.

a) 4.53 x 105 + 2.2 x 106= __________ b) 1913.0 – 4.6 x 103= __________ c) 2.34 x 1024 + 1.92 x 1023= __________

d) 2.130 x 103 – 6.6 x 102= __________ e) 9.10 x 103 + 2.2 x 106=__________ f) 1113.0 – 1.5 x 102=__________

g) 6.18 x 10-45 + 4.72 x 10-44=__________ h) 4.25 x 10-3 – 1.6 x 10-2=__________ i) 3.95 x 102 / 1.5 x 106=__________

j) (3.5 x 102)(6.45 x 1010)= __________ k) 4.44 x 107 / 2.25 x 105=__________ l) (4.50 x 10-12)(3.67 x 10-12)= __________

m) 1.05 x 10-26 / 4.2 x 1056=__________ n) (2.5 x 109)(6.45 x 104)= __________ o) 6.022 x 1023 / 3.011 x 10-56=__________

p) (6.88 x 102)(3.45 x 10-10)= __________ 5

Name Per,

Practice Worksheet: Measurements and 81gnlflcant Figures In the Lab

Making °-measurements In lhe lab requires reading a piece of lab equipment, It is your duty to not only report the measurement,but the precision of the measurement as well,

For example, examine the graduated cylinder below, The interval (value between adjacent graduations) is 1 mL The volumeon the graduated cylinder below should be recorded as 12,0 mL, since the scale can be estimated out to the tenth's place, Ifyou read it as 12 mL, you aren't communicating the precision of the scalel

im==.==,====ÿmL

15

10

Practice; Record the volume of the following graduated cylinders, Be sure to use proper sig figs, and read the bottom of themeniscus, Watch the Interval on the sca/es because they wi!l vaoL! Write the Interval In the BOX on top of each cylinder,

1mL

4O

Arts

35

,I#L

10.

mL

13

2Arts

,/nL

10

Ans

5

6ÿ mL 6,

7,5

Arts

7

mL

60.5

Arts

60

General rule: Always record the volume of a graduated cylinder __ place value more precisely than the

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Reading Instruments With Significant Figures Worksheet Name: _______________________________________ Period: _________

Please read each instrument to their limits. Include units and correct number of SigFigs.

cm

cm

⁰C ⁰C ⁰C

mL mL

mL

mL

mL

mL

mm

mm

psi kPa

7

cm

cm

⁰C K K

mL

mL

mL

mL

mL

mL

mm

kPa torr

mL

mL

mL

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