UNIT#03 GASES Flashcards

1
Q

At constant temperature when the pressure of a gas is increased three times then its volume becomes:

A

V/3
(P ∝ 1/V)

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2
Q

Under what conditions the density of an ideal gas will be maximum at:

A

➡Low temperature
➡High Pressure
(d= PV/RT)

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3
Q

If 1/V is plotted on x-axis and pressure on Y-axis at constant temperature, what should appear:

A

Straight line passing thorugh origin

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4
Q

The general gas equation to know the volumes of the gas at various temperatures is:

A

Vt = V° (1+t/273)

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5
Q

A mono-atomic substance can store energy only in the form of:

A

Translational Motion

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6
Q

A graph between pressure and product of pressure and volume at constant temperature and number of moles is:

A

Straight line parallel to x-axis

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7
Q

If both temperature and volme of a gas are doubled, the pressure

A

Remain unchanged

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8
Q

WHich one is the form of general gas equation:

A

➡PV=nRT
➡PV=RT
➡P1V1/T1 = P2V2/T2

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9
Q

Volume of a gas at S.T.P is 10dm3 at what temperature its volume will become 30dm3, keeping pressure constantWhich of the follwoing pairs of gases possess equal volume at S.T.P

A

819K
(V1T1 = V2T2)

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10
Q

Which of the follwoing pairs of gases possess equal volume at S.T.P

A

0.5 mole of NO and 16g of O2
(Equal volume of all ideal gas at same temperature and pressure contain equal number of molecules and moles)

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11
Q

Which is incorrect about ideal gas

A

➡No force of attraction between molecules❌
➡No example in nature❌
➡Can be liquified easily✅
➡Obey gas laws at all conditions of temperature and pressure❌

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12
Q

A gas initially at 27 °C is heated up to 327 °C, its average kinetic energy will be:

A

Double

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13
Q

The coorect value for geenral gas constant is:

A

8.314 x 10^7 erg mol-1 K-1

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14
Q

In gases and liquids, temperature is the measure of _____ kinetic energies of molecules.

A

Average translational

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15
Q

The molar volume of nitrogen gas is maximum at:

A

130 °C and 1 atm

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16
Q

8g of methane and 2g of hydrogen are mixed and kept at 760 mm pressure at 273K, the total volume occupied by the mixture will be:

A

33.6 dm3

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17
Q

What is NOT true about gases:

A

➡They are highly compressible❌
➡They have only vibrational motion✅
➡Sudden expansion of gases cause cooling❌
➡They exert pressure on the walls of the vessel❌

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18
Q

For a definite mass of ideal gas at constant temperature, the plot of which pair of species will give a curved graph.

A

P vs V

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19
Q

A pressure of 0.101325 bar when expressed in atmosphere represents:

A

0.1 atm
(1 atm = 1.10325 bar)

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20
Q

Dimensons of the pressure are the same as that of:

A

Force per unit volume

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21
Q

Gases deviate from ideal behaviour at high pressure. Which of the following is correct for non-ideality?

A

At high pressure, the volume of the gas becomes insignificant

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22
Q

Under high pressure which of the following gas show more ideality in character:

A

N2
Ideality of gas will be more:
➡Less Intermolcular Force
➡Smaller Size
➡Non-Polar
➡Smaller mass

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23
Q

When 200cm3 of a gas at constant pressure is heated, its volume:

A

Increases
(V ∝ T)

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24
Q

The product of PV of a gas has unit of:

A

Work
(Joule)

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25
Q

Under what condition if temperature and pressure will a real gas behave most like an ideal gas?

A

➡High Temperature
➡Low Pressure

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26
Q

Absolute temperature of a gas is direclty proportional to average ___.

A

Translational Kinetic Energy

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27
Q

An ideal gas cant be liquefied because:

A

Forces between its molecuels are negligible

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28
Q

The compressibility factor ‘Z’ for an ideal gas is:

A

Equal to one

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29
Q

In dm3 atm K-1 mol-1, 2.0 g of hydrogen gas is heated from 27 °C to 327 °C. Which of the following is incorrect

A

The number of moles of the gas increases
(closed container)

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30
Q

A pressure of a gas is due to:

A

Molecular impacts against the walls of vessel

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31
Q

The compressiiblity actor, Z i.e the extent to which a real gas deviated from ideal behaviour is given by:

A

Z= PV/RT

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32
Q

Which of the following gases has the lowest r.m.s velocity at 25 °C

A

Cl2

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33
Q

Value of a ideal gas constant R does not depend upon:

A

Units of Temperature

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34
Q

“a” is called co-efficient of attraction in Van der Waal’s equation for real gases the unit of “a” is:

A

Nm+4/mol2

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35
Q

What will be the new volume if temperature and pressure both are reduced to half

A

Remains same

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36
Q

Very small values of Van der Waal’s constant in his equation for a particular gas shows that:

A

Least attractive forces are present among the molecules of the gas

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37
Q

Excluded volume is ____ times the actual volume of gas molecules

A

Four
(b=4Vm)

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38
Q

The constant ‘a’ in Van Der Waal’s equation is maximum for:
(a=attraction per unit volume)

A

Ammonia
(Ammonia has hydrogen bonding, Strong intermolecular force)

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39
Q

The average kinetic energy of the gas molecules is:

A

Directly proprotional to its absolute temperature

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40
Q

All the collisions between the particles o gases are elastic in nature. What is meant by “elastic collision”

A

No change in the kinetic energy

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41
Q

Which one of the following expression represent the Avogadro law?

A

V=RnT/P
(When T and P are constant)

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42
Q

The root mean square velocity of gases is inversely proportional to square root of their:

A

Molar mass
c (r.m.s) = √3RT/M

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43
Q

The number of molecules in 22.4 dm3 of H2 gas at 0 °C and 1 atm are:

A

6.02 x 10^23

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44
Q

There are four gases H2, N2, He, and CO2 at 0°C. Which gas shown greater non-ideal.

A

CO2
(Mass ∝ Intermolecular Force ∝ Non-Ideal Behaviour)

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45
Q

Identify the value of R at STP:

A

0.0821 atm dm3 K-1 mole-1

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46
Q

In the Van Der Waals equation, “b” represents that:

A

Excluded volume per mole

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47
Q

Gas is enclosed in a container of 20cm3 with the moving piston. According to kinetic theory o gases, what is the effect on freely moving molecules of the gas if temperature is increased from 20°C to 100°C?Which of the following is the correct equation to calculate relative molecular mass of a gas:

A

Volume will be increased
(At constant pressure, by increasing temperature volume of a gas molecules)

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48
Q

Which of the following is the correct equation to calculate relative molecular mass of a gas:

A

M = mRT/PV

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49
Q

Which of the statmeent is applicable for both ideal and real gases molecules?

A

➡Have no forces of attraction❌
➡Collisions between the molecules is elastic❌
➡Molecules are in random motion✅
➡The actual volume of gas is negligible as compared to the volume of the gas❌

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50
Q

At absolute zero the molecules of hydrogen gas will have:

A

All the motion are ceased

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51
Q

According to the general gas euation, density of an ideal gas depends upon:

A

➡Pressure
➡Temperature
➡Molar mass of the gas
➡All of the above✅

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52
Q

The actual volume of gas molecules is considered neglegibile at following pressures.

A

2 atm

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53
Q

The unit is ___ commonly used by meterologist

A

Millibar

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54
Q

Plasma is difficult to maintain at:

A

Low Temperature

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55
Q

Effusion is the movement of a gas through extremely small opening of molecular size into region of ____ pressure.

A

Low

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56
Q

PV/nRT for an ideal gas is called

A

Compressibility Factor

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57
Q

The sum of moel fraction of the gases in a mixture of gases is:

A

Always 1

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58
Q

According to Avogadro’s law, .889 g of 1dm3 H2 and 1.4384g of 1 dm3 O2 have number of molecules

A

Same

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59
Q

Calculate the mass of 1dm3 of NH3 gas at 3°C and 1mm Hg pressure, considering that NH3 is ideally behaving

A

0.99 g

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60
Q

212-degree Farhenheit is expressed Kelvin as:

A

373

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61
Q

For non-ideal gas:

A

PV/NRT is not equal to Z

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62
Q

R does not depend upon:

A

Pressure

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63
Q

Which law is applicable while respiration:

A

Dalton’s Law

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64
Q

Which has the highest rate of diffusion:

A

NH3SO2

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65
Q

Effusions are:

A

Inversely to the square root of mass

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66
Q

KMT is discovered by:

A

Bernoulli

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67
Q

Which of these gases cannot liquify:

A

➡H2
➡He

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68
Q

The general gas equation is also known as:

A

Ideal

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69
Q

When temperature increases, the isotherm moves:

A

Away from both axis

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70
Q

Volume in an ideal gas is directly related to;

A

➡n
➡T
➡P

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71
Q

According to kinetic molecular theory absolute temperature is directly proportional to ___ of molecules.

A

Average translational kinetic Energy

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72
Q

Calculate the density of methane in g/L at -450°C and 300 torr pressure.

A

0.338

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73
Q

The general gas equation is also known as;

A

Ideal gas equation

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74
Q

The general gas equation is used for;

A

Ideal gas

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75
Q

General Gas Equation

A

PV=nRT

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76
Q

Liquids have no definite shape it is because

A

The molecules of liquid are in constant motion by sliding over each other

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77
Q

A class of materials with highly variable mechanical and optical properties that solidify from the molten state without crystallization are called

A

Amorphous solids

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78
Q

Gases deviate from Ideal behaviour at high pressure. Which of the following is correct for non idealty

A

At high pressure, the intermolecular attractions become significant

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79
Q

Under high pressure which of the following gas show more ideality in character
N2
CO2
NH3
SO2

A

N2

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80
Q

Absolute zero is

A

-459.67°F

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81
Q

The correct value of general gas constant is

A

8.314×10⁷ erg/mol.K

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82
Q

An ideal gas can’t be liquefied because

A

Forces between its molecules are negligible

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83
Q

A fire extinguisher delivers 2.2 kg of CO2. volume of CO2 at STP is

A

1120 dm3

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84
Q

When 200 ml of a gas at constant pressure is hated its volume

A

Increases

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85
Q

The product of PV of a gas is a unit of

A

Work

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86
Q

Gases exert pressure on the walls of the container because the gas molecules

A

Collide with walls of container

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87
Q

Which one of the following is absolute zeroThe number of molecules in 0.0112m3 of Methane at 0°C and pressure of 760 mm Hg is

A

Zero kelvin

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88
Q

The number of molecules in 0.0112m3 of Methane at 0°C and pressure of 760 mm Hg is

A

3.01×10^23

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89
Q

Which of the following will have same number of molecules at STP

A

280 cm3 of CO2 and 280 cm3 of N2O

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90
Q

The graph between pressure and inverse of volume at constant pressure and number of moles

A

Straight line passing through the origin

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91
Q

In a closed vessel of 1000 cm3, H2 gas is heated from 27°C to 127°C. Which statement is not correct

A

The number of moles of gas increases

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92
Q

The molecules of gas show more deviation from Ideal behaviour at low temperature because

A

Attractive force dominate at low temperature

93
Q

The gas was our best applicable under the condition

A

Low pressure and high temperature

94
Q

The root mean square velocity is expressed as

A

(3RT/M)½

95
Q

At constant pressure volume of given mass of gas is directly proportional to

A

Absolute Temperature

96
Q

Absolute zero is unattainable temperature, current attempts have resulted in the lowest temperature of

A

10–⁵ K

97
Q

If temperature is increasing continuously then constant k in PV=k will

A

Increase

98
Q

What will happen to density of an ideal gas if both temperature and pressure are doubled

A

Remain same

99
Q

100m³ of a gas at 3atm and 27°C is transferred into a container having volume 300 m³ and temperature 327°C. Pressure in new container will be

A

2 atm

100
Q

Value of general gas constant R depends on

A

Units of P and V

101
Q

Which of the molecules have maximum root mean square velocity at 25°C

A

NH3

102
Q

Which of the following gas show maximum ideal behaviour

A

N2

103
Q

The density of Methane at 2atm pressure at 27°C is

A

1.3 gdm-3

104
Q

The correct mathematical form of Avogadro’s law is

A

V1\V2=n1\n2

105
Q

The deviation of gas from Ideal behaviour is maximum at

A

-10°C and 5atm

106
Q

If Absolute Temperature is doubled and the pressure is increased to four times, the volume of gas is

A

Half

107
Q

The average kinetic energy of gas molecules is

A

Directly proportional to its Absolute Temperature

108
Q

The compressibility factor Z for an ideal gas is

A

Equal to 1

109
Q

If we increase or decrease the amount of heat to a liquid, its boiling point will

A

Remain constant

110
Q

Which is the correct order of boiling points

A

H2O >HF >NH3 >CH4

111
Q

Evaporation of water depends upon

A

Surface area and intermolecular forces
speed of air above the liquid surface
humidity in air

112
Q

110°C boiling point of water corresponds to the external pressure

A

Between 760 to1200 torr

113
Q

Boiling point of compound is mostly raised by

A

Intermolecular hydrogen bonding

114
Q

Which has greater enthalpy of vaporization

A

I2 (iodine)

115
Q

Identify incorrect statement about evaporation

A

Exothermic

116
Q

Which mathematical relationship doesn’t correctly represent behaviour of an ideal gas

A

Pressure is inversely proportional to density

117
Q

Maximum vapour pressure is shown by

A

50 cm3 ethanol and 1dm3 ethanol

118
Q

Evaporation occurs at

A

All temperatures

119
Q

Which one is the most accurate method for the measurement of vapour pressure

A

Manometric method

120
Q

The vapour pressure of methanol at 40°C is less than

A

Ether

121
Q

The volume of a given mass of gas is _____ to the inverse of the pressure

A

Direclty Proprotional

122
Q

At constant temperature, by doubling the pressure volume of gas reduced to _____.

A

1/2 of original volume

123
Q

Gases aresoluble in water at:

A

➡Low Temperature
➡High Pressure

124
Q

The SI Unit of pressure is Nm-3. 10^03 atm is equal to:

A

0.101325 KPa

125
Q

Which one has more mass at STP

A

1 dm^3 of O2

126
Q

Two gases having same temperature and pressure will have:

A

➡Same volume
➡Same no. of molecules
➡Same moles

127
Q

For a given mass with initial volume “V”, if pressure is reduced t one half and absolute temperature is increasesd two times. The volume will become;

A

4V

128
Q

Which of the following expressions at constant pressure represents Charles’s law

A

V` ∝ T

129
Q

Which of the following relation is true for the density of an ideal gas

A

PM/RT

130
Q

If absolute temperature and pressure of gas is doubled then volume o gas will:

A

Remain unchanged

131
Q

The expression for root mean square velocity is:

A

c(r.m.s) = √3/2RT/M

132
Q

16g of each of CH4 and He are in a container at 50°C. The ratio of kinetic energy is:

A

1:4

133
Q

According to kinetic molceular theory the kinetic energy of gas molecules varies directly with:

A

Absolute Temperature

134
Q

Which of the following is NOT the basic assumption of the kinetic theory of gases:

A

➡The collisions among the molecule of the gas are perfectly elastic❌
➡The molecules of the gas are always in the state of ceaseless haphhazard motion❌
➡The pressure of a gas is due to collision of gas molecules with the walls of container❌
➡The molecules exert appreciable attraction on each other✅

135
Q

In gases, Temperature is the measure of;

A

Average translational Kinetic Energy

136
Q

Observed pressure of gas on the walls of container is less than actual pressure due to:

A

Inter molecular attractive forces

137
Q

A gas that has highest value for Van der Waals coefficient of attraction

A

NH3

138
Q

A gas under what conditions will behave non-ideally:

A

➡Temperature: Low
➡Pressure; High
(At low temperature and high pressure intermolecular forces develop significantly)

139
Q

Gases deviate from ideal behaviour at high pressure. Which of the following is correct for non-ideality?

A

At high pressure, the intermolecular attraction become significant

140
Q

Which of the following shows strange behaviour when subjected to gradual increase in pressure at 0°C

A

CO2

141
Q

In Boyles law, plot between pressure and constant ‘K’ obtained is::

A

Straight Line parallel to pressure axis

142
Q

If volume of O2 is 11.2dm3 at STP, then the number of moles would be:

A

0.5 moles

143
Q

Pressure remaining constant at which temperature the volume of gas will become twice of what it is at 0°C

A

546K

144
Q

If temperature of 1 mole of gas is raised by 1K, then it would absorb ____ amount of energy.

A

0.0821 dm3 atm

145
Q

When the value of general gas constant ‘R’ us given as 8.314. The relevant units will be;

A

J. mol-1. K-1

146
Q

In the ideal gas equation PV = nRT, the value of R depends upon:

A

Units of measurement

147
Q

The gas having highest density is:

A

Cl2

148
Q

According to Kinetic theory of gases which relation is correct:

A

PV = 2/3 kT

149
Q

The molecular velocity of a gas is:

A

Proportional to root mean square velocity of a gas

150
Q

The root mean square velocity is equivalent to:

A

➡C (r.m.s) = √3RT/M
➡C (r.m.s) = √3PV/M
➡C (r.m.s) = √3P/d

151
Q

If the temperature of a gas is increased four times then its average K.E.

A

Increases 4 times

152
Q

All of the following equations are expression for the ideal gas law:

A

➡PV = nRT
➡PV/T = constant
➡P1V1/T1 = P2V2/T2

153
Q

Real gases show more deviation from ideal behaviour under which of the following conditions:

A

➡at low temperature
➡high pressure

154
Q

In Van der Waal’s equation, if the value of ‘a’ and ‘b’ are zero for a certain gas, then the gas is:

A

Ideal

155
Q

Real gases deviate at low temperature from ideal behaviour due to;

A

Significant increase in the intermolecular attractive forces

156
Q

Effective volume of molecules per mole of a gas is ____ times greater than actual volume of 1 mole of gas molecules

A

4

157
Q

The compressibility factor, (Z=PV/nRT) has value at which a gas show maximum non-ideality in behaviour:

A

1.5
(Greater the value of ‘Z’, greater the real behaviour)

158
Q

Gases exert pressure on the walls of the container because the gas molecules:

A

Collide with the walls of the container

159
Q

Which one of the following is absolute zero

A

0 K

160
Q

Crystalline solids are classified on the basis of bonding into ___ types.

A

Four

161
Q

The number of molecules in 0.0112 m^3 of methane at 0°C and pressure of 760 mm Hg is:

A

3.01 x 10^23

162
Q

Which of the following will gave the same number of molecules at STP

A

280 cm^3 of CO2 and 280 cm^3 of N2O

163
Q

The graph between pressure and inverse of volume at constant temperature and number of moles

A

A straight line passing through the origin

164
Q

In a closed vessel of 1000 cm^3, H2 gas is heated from 27°C to 127°C. Which statement is correct?

A

The number of moles of gas increases

165
Q

The molecules of gas show more deviation from ideal behaviour at low temperatures, because;

A

Attractive force dominates at low temperature

166
Q

The gas laws are best applicable under the conditions:

A

➡Low P
➡High T

167
Q

The root means square velocity is expressed as:

A

(3RT/M)^1/2

168
Q

At constant pressure, the volume of a given mass of a gas is directly proportional to;

A

Absolute temperature

169
Q

Absolute zero is an unattainable temperature, current attempts have resulted in the lowest of:

A

10^-5 K

170
Q

If the temperature is increasing continuously then constant ‘k’ in PV=k will;

A

Increase

171
Q

What will happen to the density of an ideal gas, if both temperature and pressure are doubled;

A

Remain same

172
Q

100 m^3 of gas at 3atm and 27°C is transferred into a container having a volume of 300 m^3 and a temperature of 327°C. Pressure in the new container will be;

A

2 atm

173
Q

The value of the general gas constant ‘R’ depends upon;

A

Units of P and V

174
Q

Which of the following molecules has a maximum root mean square velocity at 25°C?

A

NH3

175
Q

Which of the following gas show maximum ideal behaviour

A

N2

176
Q

Which mathematical relationship doesn’t correctly represent the behaviour of an ideal gas

A

P ∝ 1/d

177
Q

The density of methane at 2 atm pressure at 27°C is;

A

1.3 g/dm^3

178
Q

The correct mathematical form of Avogadro’s law is:

A

V1/V2 = n1/n2

179
Q

Which one is most real at STP:

A

NH3

180
Q

The deviation of gas from ideal behaviour is maximum at:

A

-10°C and 5.0 atm
(At low temperatures or high pressures, real gases deviate significantly from ideal gas behaviour)

181
Q

If the absolute temperature is doubled and the pressure is increased to 4 times, the volume of gas is;

A

Half

182
Q

The average K.E of the gas molecules is;

A

Directly proportional to its absolute temperature

183
Q

The compressibility factor (Z) for an ideal gas is;

A

Equal to one

184
Q

At constant pressure, the volume of a given mass of a gas is directly proportional to;

A

Temperature

185
Q

The volume of a gas at S.T.P is 10 dm^3 at which temperature its volume will become 30 dm^3, keeping the pressure constant

A

819 K

186
Q

Absolute zero is an unattainable temperature, current attempts have resulted in the lowest temperature of;

A

10^-5 K

187
Q

Which of the following pairs of gases possess equal volume at STP

A

➡0.5 moles of NO
➡16 g O2

188
Q

Which of the following pairs have the same rates of diffusion;

A

➡N2O
➡CO2

189
Q

Units of PV are the same as that of;

A

Energy

190
Q

If the temperature is increasing continuously then constant ‘K’ in PV=K will;

A

Increase

191
Q

What will happen to the density of an ideal gas, if both temperature and pressure are doubled;

A

Remain same

192
Q

Absolute zero is;

A

-459.4°F

193
Q

A gas initially at 27°C is heated up to 327°C, and its average K.E will be;

A

Doubled

194
Q

100m^3 of a gas at 3 atm and 27°C is transferred into a container having a volume of 300m^3 with a temperature of 327°C. Pressure in new container will ber:

A

2 atm

195
Q

Value of general gas constant ‘R” depends upon:

A

Units of P and V

196
Q

The correct value of general gas constant R is;

A

8.314 x 10^7 erg mol^-1

197
Q

The absolute temperature of a gas is directly proportional to the average;

A

Translational kinetic energy

198
Q

Which pair of gases do not obey Dalton’s law of partial pressure;

A

➡NH3
➡HCl

199
Q

The ratio of the rate of diffusion of equal volumes of He and SO2 is:

A

4:1

200
Q

NH3 gas diffuses twice faster than the gas;

A

C5H8

201
Q

At the same temperature and pressure, two balloons are separately filled with H2 and O2. If O2 escapes at the rate of 60 cm/hr, the rate of diffusion of hydrogen will be:

A

240 cm/hr

202
Q

Which of the following molecules has a maximum root mean square velocity at 25°C

A

NH3

203
Q

Two balloons are filled with equal moles of H2 and He at STP. Which balloon will contract first if the same size holes are made in both of them?

A

Ballon filled with H2

204
Q

An ideal gas can’t be liquified because;

A

Forces between its molecules are negligible

205
Q

Which of the following gas show maximum ideal behaviour

A

N2

206
Q

The SI unit of ‘a’ is:

A

Nm^4mol^-2

207
Q

The least values of Van der Waal’s constants ‘a’ and ‘b’ are for:

A

Hydrogen

208
Q

Which mathematical relationship doesn’t correctly represent the behaviour of an ideal gas?

A

➡P ∝ CT❌
➡P ∝ dT❌
➡P ∝ 1/d✅

209
Q

Which statement is correct regarding Van Der Waal’s equation:

A

a NH3 > a N2 > and b NH3 > b N2

210
Q

A fire extinguisher delivers 2.2 kg of CO2. The volume of CO2 at STP is;

A

1120 dm^3

211
Q

The ratio of partial pressure of helium to the hydrogen in a mixture of 4g o hydrogen and 4g of helium is:

A

1/2

212
Q

A mixture of 64g each of SO2, O3, O2 and CH4 is taken in a cylinder, the correct order of their partial pressure is:

A

CH4>O2>O3>SO2
(Partial Pressure ∝ No. of moles ∝ m/M)

213
Q

The number of molecules in 0.0112 m^3 of methane at 0°C and pressure 760mmHg is:

A

3.01 x 10^23

214
Q

Which of the following will have the same number of molecules at STP

A

➡280 cm^3 of CO2
➡280 cm^3 of N2O

215
Q

The partial pressure of oxygen in the lungs is;

A

116 torr

216
Q

Gases deviate from ideal behaviour at high pressure. Which of the following is correct for non-ideality:

A

At high pressure, the inter-molecular attractions become insignificant

217
Q

Evaporation is designated as a cooling process because of the reason:

A

High energy molecules leave behind the low energy molecules and cause cooling

218
Q

Evaporating water depends upon the following;

A

➡Surface area and intermolecular forces
➡Speed of the air above the liquid surface
➡Humidity of air

219
Q

The graph between and inverse of volume at constant temperature and number of moles;

A

A straight line passing through the origin

220
Q

If both the temperature and volume of a gas are doubled, the pressure

A

Remain unchanged

221
Q

In a closed vessel of 1000 cm^3, H2 gas is heated from 27°C to 127°C. Which statement is not correct?

A

➡The rate of collision increases❌
➡Pressure of gas increases❌
➡The energy of gas molecules increases❌
➡The number of moles of gas ✅

222
Q

Which one is the form of a general gas equation:

A

➡PV=nRT
➡PV=RT
➡P1V1/T1 = P2V2/T2

223
Q

The sudden expansion of the gas from high pressure towards the low-pressure causes:

A

Decrease in temperature

224
Q

The molecules of gas show more deviation from ideal behaviour at low temperatures, because

A

Attractive forces dominate at low temperature

225
Q

Which of the following temperature scale can not have a negative value:

A

Kelvin

226
Q

The gas laws are best applicable under the conditions;

A

➡Low P
➡High T

227
Q

Under high pressure which of the following gas show more ideality in character

A

N2

228
Q

Which is incorrect about ideal gas?

A

➡No force of attraction between molecules❌
➡No example in nature❌
➡Can be liquefied easily❌
➡Obey gas laws under all conditions of temperature and pressure✅

229
Q

Gases exert pressure on the walls of containers because the gas molecules:

A

Collide with the walls of the container