Scientific Measurement
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44 points possible!
The team with the most points at
the end of the period wins!
The wining team will receive 10 pts
extra credit on their assignment
sheets.
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Accuracy and Prcesion
 Describe the accuracy and precision of
each student’s measurement, the correct
mass is 47.32 g.
Trial
Lissa
Lamont
1
2
3
4
47.13
47.94
46.83
47.47
47.45
47.39
47.42
47.41
Leigh
Anne
47.95
47.91
47.89
47.93
Answer
Lissa – inaccurate and imprecise
Lamont - accurate and precise
Leigh - Anne inaccurate and precise
Maximum 3 points
Significant Figures

a.
b.
c.
d.
How many in each?
60s = 1min
47.70 g of copper
1 km = 1000m
25 computers
Answer
a.
b.
c.
d.
Infinite
4 sig figs
Infinite
Infinite
4 points
Round off to 3 Sig Figs
a.
b.
c.
d.
98.473
0.00076321 cg
57.048 m
12.17 oC
Answer
a.
b.
c.
d.
98.5
0.000763
57.0
12.2
4 points
Sig Fig Rules for Calculations
Round of each of the answers
correctly.
a. 8.7 + 15.43 + 19 = 43.13
b. 853.2 – 627.443 = 225.757
c. 38.742 / 0.421 = 92.023
d. 5.4 x 3.21 x 1.871 = 32.431914
Answer
a.
b.
c.
d.
43
225.8
92.0
32
4 points
Metric Conversions

a.
b.
c.
d.
e.
f.
Make the following conversions
157 cs = ? s
42.7 L = ? ml
261 nm = ? mm
0.065 km = ? dm
642 cg = ? Kg
8.25 x102 cg = ? ng
Answer
a.
b.
c.
d.
e.
f.
1.57 s
4.27 x 104 ml
2.61 x 10-4 mm
650 dm
0.00642 kg
8.25 x 109 ng
6 points
Density
Would the density of a person be the
same on the surface of Earth and
on the surface of the moon?
Explain.
Answer
Yes, neither the mass nor volume of
the person would change when
they went to the moon, so the
density (m/v) would remain the
same.
5 points
Scientific Notation
 Rank these numbers from
smallest to largest.
a. 5.3 x 104
b. 57 x 103
c. 4.9 x10-2
d. 0.0057
e. 5.1 x 10-3
f. 0.0072 x 102
Answer
e, d, c, f, a, b
3 points
Density
 The density of dry air measured at 25 oC
is 1.19 x 10-3 g/cm3. What is the volume
of 50.0 g of air?
D = m / V, so V = m / D
V=
5 points
50.0 g
= 4.20 x 104
1.19 x 10-3 g/cm3
Density
A tank with volume, 28.6 cm by 73.0
mm by 0.72 m is filled with olive oil.
The oil in the tank has a mass of
1.38 x 104 g. What is the density of
the olive oil in kilograms per liter?
Answer
First find the volume:
28.6 cm x 7.30 cm x 72 cm
= 15032.16 cm = 15000 cm3
Second find the density:
1.38 x 104 g / 15000 cm3
= 0.92 g / cm3
= 0.92 kg / L
10 points