• Home
  • Textbooks
  • Chemistry in 30 days
  • Gaseous State

Chemistry in 30 days

A J Prince

Chapter 2

Gaseous State - all with Video Answers

Educators

Chapter Questions

01:14

Problem 1

A gas behaves like an ideal gas at
(a) high pressure and low temperature
(b) high pressure and high temperature
(c) low pressure and high temperature
(d) low pressure and low temperature

Ajay Singhal
Ajay Singhal
Numerade Educator
01:44

Problem 2

To which of the following gaseous mixtures is Dalton's law not applicable ?
(a) $\mathrm{Ne}+\mathrm{He}+\mathrm{SO}_{2}$
(b) $\mathrm{NH}_{3}+\mathrm{HCl}+\mathrm{HBr}$
(c) $\mathrm{O}_{2}+\mathrm{N}_{2}+\mathrm{CO}_{2}$
(d) $\mathrm{N}_{2}+\mathrm{H}_{2}+\mathrm{O}_{2}$

Bridger Johnston
Bridger Johnston
Numerade Educator
01:57

Problem 3

The density of a gas at $27^{\circ} \mathrm{C}$ and $1 \mathrm{~atm}$ is $d$. Pressure remaining constant, at which of the following temperatures will its density become $0.75 d ?$
(a) $20^{\circ} \mathrm{C}$
(b) $30^{\circ} \mathrm{C}$
(c) $400 \mathrm{~K}$
(d) $300 \mathrm{~K}$

Bridger Johnston
Bridger Johnston
Numerade Educator
02:46

Problem 4

The correct order for magnitude of van der waal's constant, $b$, should be
(a) $\mathrm{C}_{2} \mathrm{H}_{5}<\mathrm{CO}<\mathrm{CO}_{2}<\mathrm{He}$
(b) $\mathrm{CO}<\mathrm{C}_{2} \mathrm{H}_{5}<\mathrm{He}<\mathrm{CO}$
(c) $\mathrm{C}_{2} \mathrm{H}_{6}<\mathrm{CO}_{2}<\mathrm{CO}<\mathrm{He}$
(d) $\mathrm{He}<\mathrm{CO}<\mathrm{CO}_{2}<\mathrm{C}_{2} \mathrm{H}_{6}$

Bridger Johnston
Bridger Johnston
Numerade Educator
02:05

Problem 5

The values of $a$ for the gases oxygen, carbondioxide, nitrogen and methane are respectively, $1.360,3.640,1.390$ and $2.253 \mathrm{~L}^{2}$ atm $\mathrm{mol}^{-1}$. Which gas can be the most easily liquefied?
(a) oxygen
(b) nitrogen
(c) carbondioxide
(d) methane

Bridger Johnston
Bridger Johnston
Numerade Educator
02:44

Problem 6

A $10 \mathrm{~L}$ cylinder of nitrogen at $4.0$ atm pressure and $27^{\circ} \mathrm{C}$ developed a leak. When the leak was repaired $2.36$ atm of nitrogen remained in the cylinder still at $27^{\circ} \mathrm{C}$. How many grams of nitrogen escaped ?
(a) $18.7 \mathrm{~g}$
(b) $0.67 \mathrm{~g}$
(c) $52.6 \mathrm{~g}$
(d) $10.0 \mathrm{~g}$

Bridger Johnston
Bridger Johnston
Numerade Educator
01:37

Problem 7

The temperature at which real gases obey the ideal gas laws over a wide range of pressures is called
(a) Critical temperature
(b) Inversion, temperature
(c) Boyle temperature
(d) Reduced temperature

Bridger Johnston
Bridger Johnston
Numerade Educator
02:32

Problem 8

At a given temperature, $\rho_{x}=3 \rho_{y}$ and $M_{y}=2 M_{x}$, where $\rho$ and $M$ stand for density and molecular mass, respectively. The ratio of their pressures $P_{I} / P_{y}$ would be
(a) $1 / 4$
(b) $4 / 1$
(c) $6 / 1$
(d) $1 / 6$

Bridger Johnston
Bridger Johnston
Numerade Educator
02:10

Problem 9

Which of the following gases will have the highest rate of diffusion ?
(a) $\mathrm{O}_{2}$
(b) $\mathrm{CO}_{2}$
(c) $\mathrm{NH}_{3}$
(d) $\mathrm{N}_{2}$

Bridger Johnston
Bridger Johnston
Numerade Educator
02:30

Problem 10

A gas in an open container is heated from $27^{\circ} \mathrm{C}$ to $127^{\circ} \mathrm{C}$. The fraction of the original amount of the gas remaining in the container will be
(a) $3 / 4$
(b) $1 / 2$
(c) $1 / 4$
(d) $1 / 8$

Bridger Johnston
Bridger Johnston
Numerade Educator
02:08

Problem 11

A I $\mathrm{dm}^{3}$ sample of air at a pressure of $1 \mathrm{~atm}$ and $27^{\circ} \mathrm{C}$ weighs $0.012 \mathrm{~kg}$. Calculate the effective molecular weight of air (in $g / \mathrm{mol}$ ) if air behaves as an ideal gas.
(a) $29.6$
(b) $30.6$
(c) $28.6$
(d) $31.6$

Bridger Johnston
Bridger Johnston
Numerade Educator
02:37

Problem 12

An open vessel at $27^{\circ} \mathrm{C}$ is heated until $3 / 8^{\text {it }}$ of the air in it has been expelled. Asumming that the volume remains constant, calculate the temperature at which the vessel was heated
(a) 307 deg $C$
(b) $107 \mathrm{C}$
(c) $480 \mathrm{C}$
(d) $207 \mathrm{C}$

Bridger Johnston
Bridger Johnston
Numerade Educator
01:26

Problem 13

If pressure of a gas contained in a closed vessel is increased by $0.4 \%$ when heated by $1^{\circ} \mathrm{C}$. its initial temperature must be
(a) $250 \mathrm{~K}$
(b) $250^{\circ} \mathrm{C}$
(c) $2500 \mathrm{~K}$
(d) $25^{\circ} \mathrm{C}$

Narayan Hari
Narayan Hari
Numerade Educator
02:11

Problem 14

At what temperature will the molar $\mathrm{KE}$ of $0.3$ mol of He be the same as that of $0.4 \mathrm{~mol}$ of argon at $400 \mathrm{~K} ?$
(a) $700 \mathrm{~K}$
(b) $500 \mathrm{~K}$
(c) $533.33 \mathrm{~K}$
(d) $400 \mathrm{~K}$

Bridger Johnston
Bridger Johnston
Numerade Educator
01:05

Problem 15

Equal masses of methane and hydrogen are mixed in an empty container at $25^{\circ} \mathrm{C}$. The fraction of the total pressure exerted by hydrogen is:
(a) $1 / 2$
(b) $8 / 9$
(c) $1 / 9$
(d) $16 / 17$

Narayan Hari
Narayan Hari
Numerade Educator
02:33

Problem 16

If $1000 \mathrm{~mL}$ of gas $\mathrm{A}$ at 600 torr and $500 \mathrm{~mL}$ of gas $\mathrm{B}$ at 800 torr are placed in a 2 litre flask, the final pressure will be:
(a) 2000 torr
(b) 1000 torr
(c) 500 torr
(d) 400 torr

Bridger Johnston
Bridger Johnston
Numerade Educator
03:51

Problem 17

A gas deviates maximum from the ideal gas laws at
(a) High temperature and high pressure
(b) Low temperature and low pressure
(c) High temperature and low pressure
(d) Low temperature and high pressure

Bridger Johnston
Bridger Johnston
Numerade Educator
01:51

Problem 18

At constant temperature, if pressure increases by $1 \%$, the percentage decrease in, volume is
(a) $1 \%$
(b) $(100 / 101) \%$
(c) $(1 / 101) \%$
(d) $(1 / 100) \%$

Aja S
Aja S
Numerade Educator
01:36

Problem 19

Two glass bulbs ' $X^{\prime}$ and $^{\prime} Y^{\prime}$ are connected by a very small tube having a stop cock. Bulb $X$ has a volume of $100 \mathrm{~cm}^{3}$ and contains the gas, while bulb $Y$ is empty. On opening the stop cock, the pressure falls down by $60 \%$. The volume of bulb $Y$ must be
(a) $150 \mathrm{~cm}^{3}$
(b) $250 \mathrm{~cm}^{3}$
(c) $100 \mathrm{~cm}^{3}$
(d) $125 \mathrm{~cm}^{3}$

Ajay Singhal
Ajay Singhal
Numerade Educator
01:09

Problem 20

The rms speed of $\mathrm{N}_{2}$ molecules in a gas is $u$. If the temperature is doubled and the nitrogen molecules dissociate into nitrogen atoms, the rms speed becomes
(a) $u / 2$
(b) $2 u$
(c) $4 u$
(d) $14 u$

Ajay Singhal
Ajay Singhal
Numerade Educator
03:42

Problem 21

Oxygen (one $\mathrm{dm}^{3}$ at 1 atm) takes 2 min to effuse through an orifice. How much time (in minutes) will be taken by $\mathrm{N}_{2}, \mathrm{He}$ and $\mathrm{SF}_{6}$ vapours to effuse under the same conditions?
(a) $0.7,1.87,4.27$
(b) $4.27,0.7,1.87$
(c) $1.87,0.7,4.27$
(d) $4.27,1.87,0.7$

Bridger Johnston
Bridger Johnston
Numerade Educator
01:51

Problem 22

Which of the following is arranged in order of increasing molecular speed?
(a) $\mathrm{HBr}<\mathrm{O}_{2}<\mathrm{N}_{2}<\mathrm{H}_{2}$
(b) $\mathrm{H}_{2}<\mathrm{N}_{2}<\mathrm{O}_{2}<\mathrm{HBr}$
(c) $\mathrm{O}_{2}<\mathrm{HBr}<\mathrm{N}_{2}<\mathrm{H}_{2}$
(d) $\mathrm{N}_{2}<\mathrm{O}_{2}<\mathrm{HBr}<\mathrm{H}_{2}$

Bridger Johnston
Bridger Johnston
Numerade Educator
02:06

Problem 23

At high pressures, the van der Waal's equation reduces to
(a) $p V=R T-\frac{a}{V}$
(b) $p V=R T$
(c) $p V=R T+p b$
(d) $p V=\frac{a R T}{V^{2}}$

Bridger Johnston
Bridger Johnston
Numerade Educator
01:42

Problem 24

In which of the following pairs of the molecules (gaseous) have the same root mean square speed ?
(a) He and $\mathrm{Ar}$
(b) $\mathrm{NO}_{2}$ and $\mathrm{N}_{2} \mathrm{O}_{4}$
(c) $\mathrm{O}_{2}$ and $\mathrm{O}_{3}$
(d) $\mathrm{N}_{2}$ and $\mathrm{CO}$

Bridger Johnston
Bridger Johnston
Numerade Educator
02:34

Problem 25

Equal masses of $\mathrm{CH}_{4}$ and $\mathrm{O}_{2}$ are mixed in an empty container at $25^{\circ}$. The fraction of the total pressure exerted by oxygen is:
(a) $1 / 3$
(b) $1 / 2$
(c) $2 / 3$
(d) $(1 / 3) \times(273 / 298)$

Bridger Johnston
Bridger Johnston
Numerade Educator
01:33

Problem 26

When a compressed gas is allowed to expand through a porous plug at a temperature above its inversion temperature, there is
(a) a fall in temperature
(b) a rise in temperature
(c) neither a fall nor a rise in temperature
(d) a fall in temperature first, followed by a rise

Bridger Johnston
Bridger Johnston
Numerade Educator
00:41

Problem 27

As temperature is raised from $20^{\circ}$ to $40^{\circ}$, the average kinetic energy of neon atoms changes by a factor of which of the following?
(a) $\frac{1}{2}$
(b) 2
(c) $\frac{313}{293}$
(d) $\sqrt{\frac{313}{293}} \mid$

Mishal Gul
Mishal Gul
Numerade Educator
01:44

Problem 28

The density of neon will be maximum at
(a) NTP
(b) $0^{\circ} \mathrm{C}, 2 \mathrm{~atm}$
(c) $273^{\circ} \mathrm{C}, 1 \mathrm{~atm}$
(d) $273^{\circ} \mathrm{C}, 2 \mathrm{~atm}$

Bridger Johnston
Bridger Johnston
Numerade Educator
02:13

Problem 29

A bottle of ammonia and a bottle of dry hydrogen chloride connected through a long tube are opened simultaneously at both ends, the white ammonium chloride ring first formed will be
(a) at the center of the tube
(b) near the hydrogen chloride bottle
(c) near the ammonia bottle
(d) throughout the length of the tube

Bridger Johnston
Bridger Johnston
Numerade Educator
01:15

Problem 30

According to the kinetic theory of gases, in an ideal gas, between two successive collisions a gas molecule travels
(a) in a circular path
(b) in a wavy path
(c) in a straight line path
(d) with an accelerated velocity

Bridger Johnston
Bridger Johnston
Numerade Educator
02:37

Problem 31

The average velocity of an ideal gas molecule at $27^{\circ} \mathrm{C}$ is $0.3 \mathrm{~m} / \mathrm{s}$. The average velocity at $927^{\circ} \mathrm{C}$ will be
(a) $0.6 \mathrm{~m} / \mathrm{s}$
(b) $0.3 \mathrm{~m} / \mathrm{s}$
(c) $0.9 \mathrm{~m} / \mathrm{s}$
(d) $3.0 \mathrm{~m} / \mathrm{s}$.

Bridger Johnston
Bridger Johnston
Numerade Educator
01:37

Problem 32

The root mean square velocity of an ideal gas at constant pressure varies with density $(d)$ as:
(a) $d^{2}$
(b) $d$
(c) $\sqrt{d}$
(d) $1 / \sqrt{d}$

Maryada Jain
Maryada Jain
Numerade Educator
02:07

Problem 33

Equal masses of $\mathrm{O}_{2}, \mathrm{CH}_{4}$ and He are present in a container. What is the mole fraction of $\mathrm{CH}_{4}$ ?
(a) $7 / 3$
(b) $2 / 11$
(c) $5 / 9$
(d) $2 / 3$

Bridger Johnston
Bridger Johnston
Numerade Educator
02:10

Problem 34

There is a mixture of $\mathrm{H}_{2}$ and He which contains $40 \%$ by mass of $\mathrm{H}_{2}$. Calculate the fraction of total pressure exerted by $\mathrm{H}_{2}$ ?
(a) $4 / 7$
(b) $3 / 7$
(c) $4 / 9$
(d) $5 / 9$

Bridger Johnston
Bridger Johnston
Numerade Educator
02:31

Problem 35

If an open vessel is heated from $27^{\circ} \mathrm{C}$ to $627^{\circ} \mathrm{C}$, what fraction of the molecules of air is left in the vessel ?
(a) $2 / 3$
(b) $1 / 3$
(c) $1 / 4$
(d) $3 / 4$

Bridger Johnston
Bridger Johnston
Numerade Educator