chapter 1 matter and measurement

Question 1

Which of the following is a pure substance? I. NaCl II. O2 III. H2O
You can choose more than one.

Answer 1

The answer is ‘ALL’ because none are mixtures containing 2 or more substances.

Question 2

Which of the following is a pure substance? Salt water, orange juice, Coca-Cola, Ammonia (NH3), or air?

Answer 2

Ammonia (NH3)

Question 3

Which of the following is a pure element? Ice, oxygen gas, aqueous hydrochloric acid, carbon dioxide gas, or sodium chloride?

Answer 3

Oxygen gas

Question 4

Which of the following is a homogeneous mixture? Liquid water, a pepperoni pizza, a can of paint, air, or liquid nitrogen?

Answer 4

Air is the correct answer.
Paint is also a mixture but will naturally separate after a while so I guess that’s what disqualifies it from being ‘homogeneous’.

Question 5

Which of the following is a chemical change? Water boiling, salt dissolving in water, metal rusting, melting iron, hail formation in the atmosphere

Answer 5

Metal rusting

Question 6

Which of the following is a physical change? Wood burning, corrosion of a copper pipe, combustion of gasoline, sublimation of dry ice (carbon dioxide), or ‘none of these’?

Answer 6

Sublimation of dry ice.
It’s pretty much just changing physical forms but skipping the liquid phase.

Question 7

Which of the following is an extensive property? Melting point, density, volume, temperature, or boiling point

Answer 7

Volume is the correct answer. An extensive property depends on the size of a sample of interest. Density is not because it is a ratio of mass to volume. ‘Mass’ is also an extensive property. Gas can be compressed but I guess you have to discount pressure being involved for this question.

Question 8

Which of the following is an intensive properety? Volume, color, mass, density, or ‘more than one of these’

Answer 8

More than one. Color and density are both indepenent of sample size.

Question 9

Which of the following is a pure element? Air, F2, NaCl, pure water, or ‘none of the above’

Answer 9

F2

Question 10

How many sig figs are there in 0.00164

Answer 10

Three.
When there are no numbers left of the decimal, zeroes immediately to the right of the decimal are not significant figures.

Question 11

How many sig figs are there in 16,000

Answer 11

Two.
With no decimal, zeroes at the end of the number are not significant.

Question 12

How many sig figs are there in 1400.01

Answer 12

Six.
Zeroes in between significant figures are significant and therefore all 3 zeroes in 1400.01 are significant.

Question 13

How many sig figs are there in 0.00170600

Answer 13

Six.
When there are no numbers left of the decimal zeroes immediately to the right of the decimal are not significant figures. But the zeroes at the end of a number to the right of the decimal are significant.

Question 14

How many sig figs are there in 720.0

Answer 14

Four.
Zeroes at the end of a number to the right of the decimal are significant.

Question 15

Convert 472 mg to grams

Answer 15

0.472 grams

Question 16

Convert 3.41 kg’s to grams

Answer 16

3,410 grams

Question 17

Convert 0.084 grams to micrograms

Answer 17

84,000 micrograms (ug)
It’s six spaces (kind of like a billion but going to the other way)

Question 18

Convert 17 grams to kg’s

Answer 18

0.017 kg’s

Question 19

Convert 62 mg’s to kg’s

Answer 19

6.2 x 10^-5

Question 20

Convert 1.8 kg’s to micrograms

Answer 20

1.8 x 10^9

Question 21

Convert 27 cm’s to meters

Answer 21

0.27 meters

Question 22

Convert 1400 meters to km’s

Answer 22

1.4 km’s

Question 23

Convert 376 nm’s to millimeters

Answer 23

3.76 x 10^-4

Question 24

Convert 13 feet to meters (1 inch = 2.54 cm’s)

Answer 24

4.0 meters (is the book’s answer)
I got 3.96

Question 25

Convert 10 lbs to grams (1 kg = 2.2 lbs)

Answer 25

4500 grams

Question 26

Convert 3m^2 to cm^2

Answer 26

30,000 cm^2 3.0m^2 times (100cm/1m)^2

Question 27

Convert 400cm^3 to m^3

Answer 27

.0004 m^3 400cm^3 times (1m/100cm)^3

Question 28

Convert 250cm^3 to liters (1cm^3 = 1ml)

Answer 28

0.25 liters

Question 29

Convert 10 inches to cm 1 inch = 2.54 cm

Answer 29

25.4 cm

Question 30

Convert 0.37 liters to nanoliters use scientific notation

Answer 30

3.7 x 10^8 nano

Question 31

A ball has a mass of 250 grams and a volume of 100cm^3 What is the density? d = m/v

Answer 31

2.5 grams per cm^3

Question 32

A block of ice has a mass of 91 grams and a volume of 100cm^3. What would be the mass of a block of ice with a volume of 20cm^3? d = m/v

Answer 32

18.2 grams solve for density of the first block. the density of ice will not change.

Question 33

A solid plastic cube with 10cm edges has a mass of 400 grams. What would be the mass of a solid cube of the same plastic with 20 cm edges?

Answer 33

3,200 grams d = m/v but you have to cube the centimeters first

Question 34

Which of the following is not a compound? NaCl, H2O, Cl2, NH4, or 'all of these are compounds'

Answer 34

Cl2

Question 35

Which of the following is not a mixture? Air, sea water, gasoline, ice, or milk

Answer 35

Ice Gas and milk are debatable to me but Ice is the only one that is obviously not.

Question 36

Which of the following always correctly describes an element? 1. Contains only one atom 2. Contains only one type of atom 3. A solution that is free of impurities 4. A pure, gaseous substance 5. Any atom or molecule that is found in nature

Answer 36

2. Contains only one type of atom

Question 37

Which of the following is not a physical change? Dissolving salt in water, sublimation of iodine, burning liquified petroleum gas, breaking a glass, or melting ice?

Answer 37

Burning petroleum

Question 38

The term 'precision' refers to...? 1. The number of decimal places the number is recorded at 2. How close measurements of the same value are to each other 3. The technical quality of the data 4. The degree to which a measurement approaches its true value 5. The absence of bias in data

Answer 38

How close measurements of the same value are to each other.

Question 39

A bicycle travels at a speed of 5m/s. What is its speed in mph? 1mile = 1.6 km

Answer 39

11.25 mph

Question 40

Convert the length 800 nanometers to millimeters

Answer 40

0.0008 mm

Question 41

What is the mass of a cube with side length 0.5 meters and density 2.4 grams per centimeter^3? d = m/v

Answer 41

300 kg You have to do a lot of converting before doing the actual math

Question 42

Which of the following has 3 sig figs? 3.4100 34.100 0.00341 0.34100 3410.0

Answer 42

0.00341

Question 43

What is 2122.03 rounded to 2 sig figs?

Answer 43

2100