CHEM 110 (Beamer)
EXAM 1 REVIEW
Last Name
Due Date
First Name
Section
M
W
ONE-STEP CONVERSIONS REVIEW
Note:
This is Practice Work. Unless I give this during lecture, this is not due for a grade.
Note:
I did not give you room on this sheet to do your work. You will need your own paper.
Relevant Exam 1 Information

Do not expect these exact problems to show up on the Exam. They will not. Memorizing the
answers and memorizing them quickly will not help you prepare. You need to understand what you
are doing.

There are no one-step conversion question in Part 1 of the Exam.

You will have all three Appendices for Part 2 of the Exam.

You must show your work for full credit

You must use units through each step.

The answer must be numerically correct.

The answer must have the exact number of significant digits correct.

The units in the answer must match the units in the work.

The Exam will have approximately five of these questions.

When practicing these questions, use the Appendices given to you. Do not go to the internet to find
the conversion factors.

Max Time: Always practice so that you are working under “max time.” You will not finish the Exam
if you are working at Max Time for every problem.
Questions
1)
12.5 teaspoons to tablespoons. Max Time: 3 min.
2)
The density of platinum metal is 21.5 g/cm 3. Calculate the volume (in cm3) of a 200.0-gram sample
platinum metal. Max time: 4 min
3)
Convert 800.0 feet to furlongs. Max Time: 4 min
4a)
Write the conversion factor between meters and micrometers. Max time: 4 min
4b)
Convert 5.0 × 10−5 meters to micrometers. You must use the metric conversion factor to solve this
problem. You cannot simply “move the decimal point.” Max time: 4 min
5)
Convert 50. calories to Joules. (Calories and Joules are units of energy). Max time: 4 min
6)
Convert 42.3751 lbs to grams. Max time: 4 min
Page 1 of 4
CHEM 110 (Beamer)
EXAM 1 REVIEW
7)
Convert 144.3 lbs to stones. Pounds (lbs) and stones are English units of weight (mass).
Max Time: 4 min
8a)
Derive the conversion factor between square meters and square gigameters. Max Time: 5 min
8b)
Convert 286 × 1015 square meters to square gigameters, using a unit factor obtained from the unit
equation in Question 8a. Max Time: 4 min
9a)
A leaky faucet in an old building drips at a rate of 0.257 milliters of water per minute. Calculate the
time (in minutes) to required for 1000. mL of water to drip from the faucet? Treat the rate of
dripping as a measured value. Max Time: 5 min
9b)
Convert your answer from Question 9a from minutes to hours. Max Time: 4 min
10)
Gas-TroTMI is a mixture of gases that is 91.5%(w/w) methane, 2.6%(w/w) sulfur dioxide, 1.7%(w/w)
hydrogen sulfide, and the rest is “unmentionable.” If a sample of Gas-TroTMI contains 420. grams of
methane, calculate the weight of the entire Gas-TroTMI sample . You may use “CH4” to represent
“methane.” Max Time: 5 min
Special Note:
Note:
You must use the dimensional analysis to solve these problems. You will receive zero credit
for “solving through simple ratios.” Example below:
Example:
Convert 0.05207 yards to inches.
Correct:
(
0.05207 yd
36 in
) (
) = x1.875 inx
1
1 yd
x
36 in
) = (
)
0.05207 yd
1 yd
No Credit:
(
Still no credit:
(36 in) (0.05207 yd) = x (1 yd)
And still no credit:
(
Nope. Not even credit
for the correct answer.
(36 in) (0.05207 yd)
x (1 yd)
) = (
)
(1 yd)
(1 yd)
x1.875 inx = x
Page 2 of 4
CHEM 110 (Beamer)
EXAM 1 REVIEW
Answers/Solutions
1)
12.5 teaspoons to tablespoons.
First, you must find the conversion factor that has both tablespoons and teaspoons.
1 tbsp = 3 tsp
(
2)
x4.17 tbspx
The density of platinum metal is 21.5 g/cm 3. Calculate the volume (in cm3) of a 200.0-gram sample
platinum metal.
(
3)
12.5 tsp
1 tbsp
) (
) =
1
3 tsp
200.0 g Pt
1 cm3 Pt
) (
) =
1
21.5 g Pt
x9.302 g Ptx
Convert 800.0 feet to furlongs.
(
800.0 ft
1 fur
) (
) =
1
660 ft
x1.212 furx
4a)
1 × 10−6 m = 1 m
4a)
Convert 5.0 × 10−5 meters to micrometers. You must use the metric conversion factor to solve this
problem. You cannot simply “move the decimal point.”
-5
(
5)
50. cal
4.184 J
) (
) =
1
1 cal
2
x210 J or 2.1 × 10 Jx
Convert 42.375 lbs to grams.
(
7)
x50. μm x
Convert 50. calories to Joules. (Calories and Joules are units of energy).
(
6)
5.0 × 10 m
1 μm
) (
) =
-6
1
1 × 10 m
42.3751 lbs
453.59 g
) (
) =
1
1 lbs
4
x1.92209 × 10 gx
Convert 144.3 lbs to stones.
(
144.3 lbs
1 st
) (
) =
1
14 lbs
x10.31 stx
Page 3 of 4
CHEM 110 (Beamer)
EXAM 1 REVIEW
Question 8: Total of 13 points
1 min to find raw conversion factors

Timing:
(Mastery = A):
1 min 30 s to derive squared conversion factor
3 min
1 min to solve/write answer
1 min to find raw conversion factors
Timing:
(Competence = C):
2 min 30 s to derive squared conversion factor
5 min
2 min to solve/write answer
5 pt (Deriving the squared conversion factor)
1 × 109 m = 1 Gm
8a)
9
2
18
2
1 pt ( raw conversion factor – all or nothing – units must be included)
2
(1 × 10 m) = (1 Gm)
1 × 10
8b)
(
286 × 10
1
m
15
m2
= 1 Gm
1 pt (Show work for squaring both sides)
2
3 pt (Correct math and units)
2
)
(
1 Gm
1 × 10
18
m2
)
=
2
x0.286 Gm x
1 pt
2 pt
initial value
correct unit
3 pt (final answer point breakdown)

1 pt: correct numerical answer
factor

1 pt: correct number of sigdigs

1 pt: units in answer must match
2 pt: units shown through every step.
units in your work
9a)
A leaky faucet in an old building drips at a rate of 0.257 milliliters of water per minute. Calculate the
time (in minutes) to required for 1000. mL of water to drip from the faucet? Treat the rate of
dripping as a measured value.
(
9b)
x3890 min
or
3
3.90 × 10 minx
Convert your answer from Question 9a from minutes to hours.
(
10)
1000. mL
1 min
) (
) =
1
0.257 mL
3890 min
1 hr
) (
) =
1
60 min
x64.8 hrx
Gas-TroTMI is a mixture of gases that is 91.5% methane by weight, 2.6% sulfur dioxide, 1.7%
hydrogen sulfide, and the rest is “unmentionable.” If a sample of Gas-TroTMI contains 420. grams of
methane, calculate the weight of the entire Gas-TroTMI sample . You may use “CH4” to represent
“methane.”
420. g CH4
100 g Gas-Tro
(
) (
1
91.5 g CH4
TMI
) =
x459 g Gas-Tro
TMI
x
Page 4 of 4