PRE-AP CHEMISTRY DIMENSIONAL ANALYSIS WORKSHEET #1 Metric Practice 1. 765km = __________ mm 2. 3.45 x 10-3kg = ______ng 3.

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Transcript PRE-AP CHEMISTRY DIMENSIONAL ANALYSIS WORKSHEET #1 Metric Practice 1. 765km = __________ mm 2. 3.45 x 10-3kg = ______ng 3.

PRE-AP CHEMISTRY
DIMENSIONAL ANALYSIS
WORKSHEET #1
Metric Practice
1. 765km = __________ mm
2. 3.45 x 10-3kg = ______ng
3. 0.0239 g = ________g
Helpful steps:
1.
2.
3.
4.
Circle all conversion factors/ratios you see in the problem
The number you have not circled can indicate to you where to start.
May need to use other conversion factors not listed in problem.
If you only have one number, start with it.
1. The acid in an automobile battery (a
solution of sulfuric acid) has a density of
1.2 g/cm3. What is the mass of 2.00 x 102 mL
of this acid?
2.00 x 102ml 1 cm3 1.2g
1 mL 1 cm3
= 240g
2.If Jules Verne expressed the title of his
famous book, Twenty Thousand Leagues under
the Sea in basic SI units, what would the title
be? (1 league = 3.45 mi, 1 mi = 1609 m)
20,000 Leagues 3.45 mi 1609 m
1 league 1 mi
= 1.11 x 108
=1 x 108 m
One Hundred Million Meters under the Sea
3.A few years ago, a cartoon pictured a thief
making his getaway, gun in one hand and a bucket
of gold dust in the other. If the bucket had a
volume of 8.00 qt. and was full of gold whose
density is 19.3 g/cm3, what was its mass?
Comment on the thief's strength. (1.057 qt = 1 L)
8.00qt 1L
1000 cm3 19.3g
1.057qt 1L
1 cm3
= 1.46 x 105g
(about 322 pounds)
The thief was very strong!!!!
4. What is the cost in dollars for the nails used to
build a fence 125 meters long if it requires
30 nails per meter?
Assume that 40 nails are sold per box at a cost of
75 cents per box.
125m 30nails 1 box $0.75
1m
40 nails 1 box
= $70.31
or since we can’t buy part of a box of nails,
$70.50
5.A light-year is the distance that light can
travel in one year. If the sun is 1.5 x 108 km
away, how many light years is the sun from
earth? Assume that light travels at a speed of
3.0 x 1010 cm/s.
1.5 x 108 km 1000m 100cm 1 s
1 min 1 hr 1 day 1 year
1 km 1 m 3.0 x 1010cm 60s 60min 24 hr 365 day
=
1.6 x 10-5 years
6.A budding young chemist decided to throw tradition overboard
and include time in the metric system. To do this, she kept the unit
"day" to refer to the usual 24-hour time interval we know. She then
subdivided the day into centidays, millidays, and microdays. Solve
the following problems, rounding them each to three significant
digits:
A. A 100 yd dash done in 9.7 s took how many
microdays?
9.7s 1 min 1 hr 1 day
1 x 106 µday
60s
60 min 24 hours 1 day
= 112 µday
B. A 50 min class period lasts for how many
centidays?
50 min 1 hr
1 day 100cday
60 min 24 hr 1 day
= 3.47 cdays
C. A car going 60 mph goes how many miles
per centiday?
60 mi 24 hr 1 day
1 hr 1 day 100cday
= 14.4 miles/cday
D. What is the velocity of light in miles per
milliday if it is 186,000 mi./s?
186000 mi 60 s 60 min 24 hr 1 day
1s
1 min 1 hr 1 day 1 x 103 mday
= 1.61 x 107 mi/mday
E. What is the acceleration of gravity in
centimeters per microday2 if it is 980 cm/s2
980 cm (60)2s2 (60)2min2 (24)2hr2 1day2
1s2
1 min2 1hr2
1day2 (1 x 106)2µday2
= 7.32 cm/ µday2