Gases

Question 1

is a measure of the change in volume of a sample of matter resulting from a pressure change.

Answer 1

compressibIlity

Question 2

is a measure of the change in volume of a sample of matter resulting from a temperature change.

Answer 2

thermal expansion

Question 3

set of five statements used to explain the physical behavior
of the three states of matter (solids, liquids, and gases).

Answer 3

kinetic molecular theory of matter

Question 4

is energy that matter possesses because of particle motion.

Answer 4

kinetic energy

Question 5

is stored energy that matter possesses as a result of its position, condition, and/or composition

Answer 5

potential energy

Question 6

Five Statements of KMT

Answer 6

1. Matter is ultimately composed of tiny particles (atoms, molecules, or
   ions) that have definite and characteristic sizes that do not change.
2. The particles are in constant random motion and therefore possess kinetic energy.
3. The particles interact with one another through attractions and repulsions and therefore possess potential energy.
4. The kinetic energy (velocity) of the particles increases as the
   temperature is increased.
5. The particles in a system transfer energy to each other through elastic collisions.

Question 7

is the physical state characterized by a complete dominance of kinetic energy (disruptive forces) over potential energy (cohesive forces).

Answer 7

gas

Question 8

is the physical state characterized by potential energy (cohesive forces)
and kinetic energy (disruptive forces) of about the same magnitude.

Answer 8

liquid

Question 9

is the physical state characterized by a dominance of potential energy (cohesive
forces) over kinetic energy (disruptive forces).

Answer 9

solid

Question 10

Identify the physical state described below:
1. definite volume and shape
2. high density
3. small compressibility
4. very small thermal expansion

Answer 10

solid

Question 11

Identify the physical state described below:
1. definite volume and indefinite shape
2. high density
3. small compressibility
4. small thermal expansion

Answer 11

liquid

Question 12

Identify the physical state described below:
1. indefinite volume and shape
2. low density
3. large compressibility
4. moderate thermal expansion

Answer 12

gas

Question 13

is a generalization that describes in mathematical
terms the relationships among the amount, pressure, temperature, and volume of a gas.

Answer 13

gas law

Question 14

Occurrence of Gases: Composition of air by volume

Answer 14

78% N2
21% O2
1% of other gases

Question 15

Abundance of elements: composition of the universe

Answer 15

91% Hydrogen
9% Helium
<0.1% Others

HY HELIUM

Question 16

Abundance of elements:
earth’s crust

Answer 16

Oxygen 47%
Silicon 28%
Aluminum 8%
Iron 5%
Others 12%

OXSILAFE

Question 17

Abundance of elements:
Human Body

Answer 17

65% Oxygen
18% Carbon
9.5% Hydrogen
3.2% Nitrogen
4.3% Others

OX KA? HYDNI

Question 18

a substance that is gaseous state at ordinary temperatures and pressures

Answer 18

gas

Question 19

is the gaseous form of a substance that is usually a liquid or solid under those conditions

Answer 19

vapor

Question 20

the force applied per unit area

Answer 20

pressure

Question 21

what is 1 newton (N) equal to?

Answer 21

1N = 1 kgm/s^2

Question 22

what is 1 Pa equal to?

Answer 22

1Pa = 1N/m^2

Question 23

is the pressure exerted by the Earth’s atmosphere

Answer 23

atmospheric pressure

Question 24

the force exerted by the weight of the air above us

Answer 24

atmospheric pressure

Question 25

instrument for measuring pressure

Answer 25

barometer

Question 26

is equal to the pressure that supports a column of mercury exactly 760nm high at 0oC at sea level

Answer 26

standard atmospheric pressure

Question 27

The pressure outside a jet plane fl ying at high altitude falls considerably below standard atmospheric pressure. Therefore, the air inside the cabin must be pressurized to protect the passengers. What is the pressure in atmospheres in the cabin if the barometer reading is 688 mmHg?

Answer 27

0.905 atm

Question 28

The atmospheric pressure in San Francisco on a certain day was 732 mmHg. What was the pressure in kPa?

Answer 28

97.6 kPa

Question 29

CONVERSION FACTOR: 1 atm is equal to ______ bar

Answer 29

1.01325 bar

Question 30

CONVERSION FACTOR: 1 atm is equal to ______ Pa

Answer 30

101,325 Pa

Question 31

CONVERSION FACTOR: 1 atm is equal to ______ kPa

Answer 31

101.325

Question 32

CONVERSION FACTOR: 1 atm is equal to ______ mmHg

Answer 32

760

Question 33

CONVERSION FACTOR: 1 atm is equal to ______ torr

Answer 33

760

Question 34

is a device used to measure the pressure of gases other than the atmosphere.

Answer 34

manometer

Question 35

CONVERSION FACTOR: 1 L is equal to ______ mL

Answer 35

1000

Question 36

CONVERSION FACTOR: 1 mL is equal to ______ cm^3

Answer 36

1 cm^3

Question 37

the volume of a fixed amount of a gas is inversely proportional to the pressure applied to the gas if the temperature is kept constant.

Answer 37

Boyle's law

Question 38

CONVERSION FACTOR: 1 m3 is equal to ______ dm^3

Answer 38

1000 dm^3

Question 39

CONVERSION FACTOR: 1 bar is equal to ______ Pa

Answer 39

10^5 Pa

Question 40

property that describes the flow of energy when 2 objects are in contact or between a thermally conducting rigid wall

Answer 40

temperature

Question 41

property that is defined as the amount of matter

Answer 41

number of moles

Question 42

property that is defined as the space occupied by a system

Answer 42

volume

Question 43

a model gas system that approximates gas behavior at LOW PRESSURES AND HIGH TEMPERATURES

Answer 43

Ideal gas

Question 44

IUPAC Standard Temperature and Pressure (STP)

Answer 44

273.15K and 1 bar

Question 45

What gas law describes the mathematical expression law below? P ∝ 1/V

Answer 45

Boyle's Law

Question 46

What gas law describes the mathematical expression law below? V ∝ T

Answer 46

Charles' Law

Question 47

What gas law describes the mathematical expression law below? V ∝ n

Answer 47

Avogadro's Law

Question 48

What gas law describes the mathematical expression law below? P ∝ T

Answer 48

Gay-Lussac's Law

Question 49

states that the volume of a fixed amount of gas maintained at constant pressure is directly proportional to the absolute temperature of the gas.

Answer 49

Charles' Law

Question 50

states that at constant pressure and temperature, the volume of a gas is directly proportional to the number of moles of the gas present.

Answer 50

Avogadro's Law

Question 51

Combined Gas Law Formula

Answer 51

(P1V1)/T1 = (P2V2)/T2

Question 52

describes the relationship among the four variables P, V, T, and n

Answer 52

Ideal gas equation

Question 53

Ideal gas law

Answer 53

PV=nRT

Question 54

Formulae for getting the density from the gas law

Answer 54

rho = PM/RT

Question 55

Formulae for getting the molar mass from the gas law

Answer 55

M= mRT/PV

Question 56

Universal Gas Constant

Answer 56

0.0821 L-atm/mol-k 8.314 J/mol-k

Question 57

The total pressure of a mixture of gases is equal to the sum of the partial pressures of the individual gases

Answer 57

Dalton's Law of Partial Pressures

Question 58

is a dimensionless quantity that expresses the ratio of the number of moles of one component to the number of moles of all components present.

Answer 58

mole fraction

Question 59

Mole fraction formula:

Answer 59

Xf = ni/nt

Question 60

If a system contains more than two gases, then the partial pressure of the i th compo- nent is related to the total pressure by

Answer 60

Pi = XiPt

Question 61

Sulfur hexafluoride (SF ) is a colorless, odorless, very unreactive gas. Calculate the pressure (in atm) exerted by 1.82 moles of the gas in a steel vessel of volume 5.43 L at 69.5°C.

Answer 61

9.42 atm

Question 62

Calculate the volume (in liters) occupied by 7.40 g of NH 3 at STP.

Answer 62

9.74L

Question 63

An infl ated helium balloon with a volume of 0.55 L at sea level (1.0 atm) is allowed to rise to a height of 6.5 km, where the pressure is about 0.40 atm. Assuming that the temperature remains constant, what is the final volume of the balloon?

Answer 63

1.4L

Question 64

Calculate the density of carbon dioxide (CO2) in grams per liter (g/L) at 0.990 atm and 55 C.

Answer 64

1.62g/L

Question 65

A chemist has synthesized a greenish-yellow gaseous compound of chlorine and oxygen and finds that its density is 7.71 g/L at 36°C and 2.88 atm. Calculate the molar mass of the compound and determine its molecular formula.

Answer 65

67.9 g/mol

Question 66

Chemical analysis of a gaseous compound showed that it contained 33.0 percent silicon (Si) and 67.0 percent fl uorine (F) by mass. At 35°C, 0.210 L of the compound exerted a pressure of 1.70 atm. If the mass of 0.210 L of the compound was 2.38 g, calculate the molecular formula of the compound.

Answer 66

Si2F6

Question 67

Determine the molar mass of an unknown gas if a sample weighing 0.389g is collected in a flask with a volume of 102 cm^3 at 97°C. The pressure of the gas is 728 mmHg.

Answer 67

a) 187g/mol b) 121g/mol c) 112g/mol d) 31.6 g/mol

Question 68

There are 135 L of gas in a container at a temperature of 2600°C. If the gas was cooled until the volume decreased to 75 L, what would the temperature of the gas be?

Answer 68

296K or 23°C

Question 69

The initial volume of a gas at a pressure of 3.2 atm is 2.9 L. What will the volume be if the pressure is increased to 4.0 atm?

Answer 69

2.3L

Question 70

Two flasks are connected with a stopcock. Flask #1 has a volume of 2.5 L and contains oxygen gas at a pressure of 0.70 atm. Flask #2 has a volume of 3.8 L and contains hydrogen gas at a pressure of 1.25 atm. When the stopcock between the two flasks is opened and the gases are allowed to mix, what will the resulting pressure of the gas mixture be?

Answer 70

0.28 atm + 0.5 atm = 1.0 atm