Gases Flashcards
(74 cards)
1
Q
What is the major difference between the states of matter?
A
The arrangement of particles
2
Q
Solid have
A
Definite volume
Definite Shape
3
Q
Liquid have
A
Definite volume
Indefinite shape
4
Q
Gas have
A
Indefinite volume
Indefinite shape
4
Q
What is the physical significance of having the gas’ arrangement of particles?
A
It is compressible
5
Q
The volume of a gas changes significantly with:
A
Pressure, temperature, gases flow freely, gases generally
6
Q
Characteristics of gases
A
Gases flow freely, gases generally mix in all proportions
7
Q
Major Characteristics of gases
A
Expansibility
Compressibility
Pressure
Effect on heat
Diffusibility
8
Q
The collision of gases particles on the walls of the container gives rise to
A
Pressure
9
Q
SI unit of pressure
A
Pascal
10
Q
Formula for pressure
A
Force/ area
11
Q
This may either be in terms of grams or moles
A
Amount
12
Q
SI unit of amount
A
Moles
13
Q
Formula for amount of substance
A
Grams/ molar mass
14
Q
The amount of space that is to be occupied by gaseous state
A
Volume
15
Q
SI unite of volume
A
Cubic meter
16
Q
Relates to the average kinetic energy of gaseous particles
A
Temperature
17
Q
SI unit of temperature
A
Kelvin
18
Q
Celsius to Fahrenheit
A
(9/5 x C) + 32
19
Q
Fahrenheit to Celsius
A
(5/9 x F) - 32
20
Q
A parameter that describes gases, which have an SI unit of Joule
A
Energy
21
Q
equivalent of 1 cal to joule?
A
4.184 J
22
Q
What is the values for Universal Gas Constant in correct units?
A
8.314 J/ mol K
0.08205 L atm/ mol K
1.986 cal/ mol K
23
Q
Pressure in STP
A
1 atm/ 101.3 kPa
24
Temperature in STP
0 C/ 273.15 K
25
Molar volume in STP
22.4 L/ atm
26
No. of moles in STP
1 mol
27
Enumerate the 5 kinetic molecular theory of gases
1. Gases travel in straight lines and random directions
2. Small particle sizes to be negligible
3. Atomic collision are perfectly elastic, KE is conserved
4.Gas particles do not repel or attract
5. KE of gas is directly proportional to Kelvin Temperature
28
What are the parameters that describes gases
Pressure, temperature, amount, volume
29
Describe charles law and formula
States that there is a direct relationship between the gas volume and temperature
V1/T1 = V2/T2
30
Describe boyles law and formula
States that there is an indirect relationship between the gas volume and pressure
V1P1 = V2P2
31
Describe Gay-lussac law and formula
States that there is a direct relationship between the gas pressure and temperature
P1/T1 = P2/T2
32
Describe avogadros law and formula
States that there is a direct relationship between the gas volume and number of moles
V1/N1 = V2/n2
33
The total pressure of a mixture of gases is equal to the sum of the pressures of all the gases present.
Daltons Law of Partial Pressure
34
Give formula of Partial Pressure
P total = (n1 + n2 + n3 ...) (RT/V)
35
Phenomena which results in the net
movement of particles from a region
of high concentration to a region of
low concentration in response to a
concentration gradient
Graham's law of diffusion
36
Under same conditions of constant temperature and pressure, the rates of diffusion of different gases are ____________ to the square roots of
their molecular masses.
inversely proportional
37
Formula for Grahams law of diffusion
rate2/rate1 = Square root M1/M2
38
net movement of particles through
an opening smaller than the mean
free path of the gas (no collisions)
Effusion
39
net movement of particles from a
region of high to low concentration
as influenced by collisions
Diffusion
40
Formula for Graham law of effusion
Effusionrate2/ Effusionrate1 = Square root M1/M2
41
Formula for average KE of a gas molecule
e = 3RT/ 2N0
42
In deriving the kinetic gas equation, what
was the assumption made regarding the
velocities of the gaseous molecules?
Constant velocity for all molecules.
43
The velocity place in the utmost peak in of molecular velocity graph
Most probable velocity
44
Located after the most probable velocity
average velocity
45
The farthest velocity from the most probable velocity
Root mean square velocity
46
Distance travelled by a molecule between two successive collisions
THE MEAN FREE PATH
47
Relationship of mean free path to
pressure;
volume; and
temperature
Indirectly Proportional
Indirectly Proportional
Directly Proportional
48
If collision diameter is large, mean free path will _____
Smaller
49
Relationship of collision diameter to the mean free path
If collision
diameter is large, mean free path will be smaller!
50
amount of heat required to raise the temperature of one gram of a substance by 1°C
may be measured at constant volume or constant pressure
Specific Heat Ratio of Gases
51
The Vibrational and rotational degrees of freedom in monoatomic gases
Zero
52
volume kept constant while allowing pressure to increase
Specific Heat at Constant Volume
53
pressure kept constant while allowing volume to increase
Specific Heat at Constant Pressure
54
Two applications of heat in Specific Heat at Constant Pressure
1. Increase KE of molecules
2. Performing expansion work
55
What specific conditions do ideal gases work in?
High temperature
Low pressure
56
The deviation of the compression factor from unity is a measure of
Nonideality of gas
57
At very low pressures, Z will be
approximately ____ for all the gases
1
58
Deviation from ideality becomes
much _____ at high temperatures
lesser
59
At low pressures and high temperatures, real gases approach _____ and so obey the ideal gas equation
ideality
60
At low temperatures and sufficiently high pressures, the gas behaves as
Real gas
61
Larger deviations are primarily observed when the gas is closer to its
liquefaction point
62
Ideality satisfied at ____
temperatures and ____ pressures
high, low
63
Because of the existence of attractive forces, pressure is ______ for a real gas
lesser
64
Since the non-volume postulate is no longer valid, volume is _____ for a real gas
Larger
65
Related to
the effective /excluded volume
van der Waal’s Constants, b
66
Related to the strength of the
interactions between your molecules
van der Waal’s Constants, a
67
When gases are compressed, it
Liquefies
68
Temperature above which it cannot be liquefied no matter how much pressure is applied
CRITICAL TEMPERATURE, Tc
69
Minimum pressure required to liquefy the gas at its critical temperature
CRITICAL PRESSURE, Pc
70
Volume occupied by a mole of the gas at the critical temperature and critical pressure.
CRITICAL VOLUME, Vc
71
When a gas is at its critical temperature and critical pressure the gaseous and liquid phase lose their discernible boundary
(known as the critical phenomenon) and the gas is in its
critical state
72
What are the 5 Kinetic Molecular Theory of Gases
1. Gases travel in straight lines and in random directions
2. Gases particles are so small that their size is negligible
3. Atomic or molecular collisions are perfectly elastic and so kinetic energy is conserved
4. The gas particles are assumed not to attract or repel each other.
5. The average kinetic energy of the gas particles is directly proportional to the Kelvin temperature.
73
In deriving the kinetic gas equation, what was the assumption made regarding the velocities of the gaseous molecules?
.
Constant velocity for all molecules
