Metrics, Significant
Figures, Conversions, and
Density
Review! YEAH!

How Many Significant Figures Do
I Have?


3.12050
6
• 0.0101010100
•9


4.05
3
• 300
•1


0.0020
2
• 300.
•3

Question Two

457 km = ________ cm

Move decimal 5 to the right: 45,700,000

Question Three

14.6 yards = ____ ft

14.6 yds x 3ft/1yd =
43.8 ft

Question Four

Add, using correct significant figures
3.492 + 0.303 + 30.30

34.10

Question Five

37,854,120 mL =
______ L

Move decimal 3 to the left, 37854.12 No zero because of sig figs

Question 6

If the mass of an object is 124.589 grams and the density is 2.45 g/cm 3 , what is the volume of the object?

124.589/2.45 = 50.9 cm 3

Question 7

30,833 mg = ____ kg

Move decimal six to the left

0.030833 kg

Question Eight

5 m L = _____ mL

Move decimal 3 to the left

0.005 mL

Question Nine

The density of an object is 1.56 g/cm 3 . What is the mass of this object when the volume is 12
L?

Convert 12L  mL

1.56 x 12,000 = 19,000 g

Question Ten

1.25 days = _______ s

1.25 days x 24 hours x 60 min x 60 sec = 108000 s

Question Eleven

If I am measuring with a ruler in centimeters, how many digits past the decimal should I record?

2

Question Twelve

How do I find the volume of a rectangular solid?

L x W x H

Question Thirteen

I took the mass of a block of wood. The mass was 198 mg.
I then measured the block and it was 14 cm wide, 3 cm high, and 17 cm long. What is the density of the wood?

Multiply L x W x H to get volume

0.198/714 = 0.0003 g/cm 3

Question Fourteen

160 km 2 = _____ m 2

Normally you would move three to the right, but since it’s squared you’d do that twice… so 6 to the right

1.6 x 10 8 m 2

Question Fifteen

156 cm 3 = _____ m 3

Normally you would move two to the left, but since it’s cubed, you do that three times, so move six to the left

1.56 x 10 -4 m 3

Question Sixteen

One of the largest gold nuggets ever discovered was found in Australia in 1872.
The nugget had a mass of 286 kg. Given that 19.32 g/cm 3 is the density of gold, calculate the volume of this nugget

Convert 286kg  286000 g

286000 / 19.32 = 14800 cm 3

Question Seventeen

I am measuring the length of a stirring rod and I get: 1.25 cm,
12.8 mm, and 0.129 m. The actual length of the stirring rod is
19.3 cm. Am I accurate? Am I precise?

You are not accurate because you did not get the correct number. You are also not precise because all measurements are not close to each other when converted.

Question Eighteen

I am measuring the mass of sodium chloride for an experiment. I obtain a measurement of 12.236 mL.
What is wrong with the way
I have reported this value?

Mass should be in units of grams, not milliliters

Question Nineteen

48°C = _____°F

°F = 9/5°C + 32

9/5*48+32 = 120°F

Question Twenty

115°F = ______ K

°C = 5/9(°F -32)

5/9(115-32) = 46.1°C

K = °C + 273

46.1 + 273 = 319 K

Question Twenty - One

Express
125,000,000,000 in scientific notation

1.25 x 10 11

Question Twenty Two

Express 0.0000008 in scientific notation

8 x 10 -7

Question Twenty Three

What is 4.869 x 10 5 in decimal notation?

486,900

Question Twenty Four

What is 5.21 x 10 -4 in decimal notation?

0.000521

Question Twenty Six

298 K = ____°F

298K-273 = 25°C

9/5(25)+32 = 77.0°F

Question Twenty seven

How many significant figures do I have?
12,000,000

2

Question Twenty Eight

How many significant figures do I have?
10.0

3

Question Twenty Nine

A sample has a volume of 12.5 L and a mass of 25.8 kg. What is its density in g/L?

25,800/12.5 = 2060 g/L

Question Twenty Nine

A student finds the density of carbon monoxide to be
1.62 g/cm 3 . The accepted value is 1.12 g/cm 3 . What is the percent error?

|1.12-1.62| / 1.12 x 100 = 44.6%

Question Thirty

One inch = 2.54 cm

15.869 cm 3 = ____ in 3

15.869 cm x 1/2.54 x 1/2.54 x 1/2.54 = 0.96839 in 3

Question Thirty One

If I am driving in a car at 65 miles/hour, what is my speed in meters/second

1 mile = 1.6 km

65 miles x 1.6 km/mile x 1000 m/km x 1hr/60min x 1min/60 sec
= 29 m/s

Question Thirty Two

I am measuring the mass of calcium chloride for an experiment. I measure the mass three times, obtaining values of 125.46 g, 0.12455 kg, 124,999 mg. The actual mass is 1.25 x 10 8 m g. Am I accurate? Am I precise?

You are both accurate and precise

Question Thirty Three

I measure the volume of a liquid to be 124.56 mL. The actual volume is 12.8 cL.
What is my percent error?

Convert to the same unit first!

|12.8 – 12.456| / 12.8 x 100 =
2.69%

Question Thirty Four

Convert 6.5 x 10 7 nm to cm.

Nano to centi is seven to the left

6.5 cm

Question Thirty Five

87 mm 2 = ____ dm 2
 mm to dm is usually two steps to the left. Since it’s squared, you’ll move four spots to the left.

0.0087

Question Thirty Six

Add, using proper sig figs

5.0385 + 8.9 + 14.203 =

28.1

Question Thirty Seven

The density of an object is 5.46 g/cm 3 . Calculate the volume, in liters, of an object that has a mass of 540 mg.

9.9 x 10 -5 L

Question Thirty Eight

The mass of an object is
65 dg. The density of the object is 4.392 g/L.
What is the volume of the object in mL?

1500 mL


Don’t forget to study your equipment and reading equipment!!