A piston filled with 0.04 mol of an ideal gas expands reversibly from 50.0 mL to 375 mL at a constant temperature of 3 7 . 0 ∘ C . As it does so, it absorbs 208 J of heat. The values of q and w for the process will be (R = 8.314 J/mol K) (ln7.5 = 2.01)

q = + 2 0 8 J , w ⁡ = - 2 0 8 J

q = + 2 0 8 J , w ⁡ = + 2 0 8 J

q = - 2 0 8 J , w ⁡ = - 2 0 8 J

For one mole of a van der Waals' gas, the compressibility factor Z = p V R T at a fixed volume will certainly decrease, if [Given : " a " and " b " are standard parameters for van der Waals' gas]

" b " decreases and " a " increases at constant temperature

" b " increases and " a " decreases at constant temperature

temperature increases at constant a n and " b " values

" b " increases at constant " a " and temperature

HARD

Earn 100

The isotherms of a gas are shown below :

Among the following,

(i) At $T_{1}$ , the gas cannot be liquefied

(ii) At point $B$ , liquid starts to appear at $T_{2}$

(ii) $T_{C}$ is the highest temperature at which the gas can be liquefied

(iv) At point $A$ , a small increase in pressure condenses the whole system to a liquid

The correct statements are :

50% studentsanswered this correctly

Important Questions on States of Matter

EASY

Chemistry>Physical Chemistry>States of Matter>Behaviour of Real Gases

A piece of ice falls from a height

h

so that it melts completely. Only one-quarter of the heat produced is absorbed by the ice and all energy of ice gets converted into heat during its fall. The value of

h

is:
(Latent heat of ice is

3.4 \times 10^{5} {J kg}^{- 1}

and

g = 10 {N kg}^{- 1}

)

EASY

Chemistry>Physical Chemistry>States of Matter>Behaviour of Real Gases

In the following compressibility factor (Z) vs pressure graph at 300 K, the compressibility of

C H_{4}

at pressure < 200 bar deviates from ideal behavior because

Question Image

MEDIUM

Chemistry>Physical Chemistry>States of Matter>Behaviour of Real Gases

If a gas expands at constant temperature it indicates that

MEDIUM

Chemistry>Physical Chemistry>States of Matter>Behaviour of Real Gases

The combination of plots which does not represent isothermal expansion of an ideal gas is

$(A)$ Question Image

$(B)$

$(C)$

$(D)$

MEDIUM

Chemistry>Physical Chemistry>States of Matter>Behaviour of Real Gases

Which of the following gases has high Boyle's temperature?

HARD

Chemistry>Physical Chemistry>States of Matter>Behaviour of Real Gases

An ideal gas undergoes isothermal compression from

5 m^{3}

1 m^{3}

against a constant external pressure of

4 N m^{- 2}

. The heat released in this process is

24 J {mol}^{- 1} K^{- 1}

and is used to increase the pressure of

1

mole of

Al

. The temperature of

Al

increases by:

MEDIUM

Chemistry>Physical Chemistry>States of Matter>Behaviour of Real Gases

The correct order of compressibility is:

MEDIUM

Chemistry>Physical Chemistry>States of Matter>Behaviour of Real Gases

A system consisting of 1 mol of an ideal gas undergoes a reversible process,

A \to B \to C \to A

(schematically indicated in the figure below). If the temperature at the starting point A is 300 K and the work done in the process

B \to C

is 1 L atm, the heat exchanged in the entire process in L atm is

Question Image

EASY

Chemistry>Physical Chemistry>States of Matter>Behaviour of Real Gases

For an ideal gas, the compressibility factor is

EASY

Chemistry>Physical Chemistry>States of Matter>Behaviour of Real Gases

A certain gas obeys

P (V_{m} - b) = RT

. The value of

{(\frac{\partial Z}{\partial P})}_{T}

\frac{xb}{RT}

. The value of

x

is (Integer answer) (

Z

: compressibility factor)

HARD

Chemistry>Physical Chemistry>States of Matter>Behaviour of Real Gases

A reversible cyclic process for an ideal gas is shown below. Here,

P, V, a n d T

are pressure, volume and temperature, respectively. The thermodynamic parameters

q, w, H a n d U

are heat, work, enthalpy and internal energy, respectively.

Question Image

The correct option(s) is (are)

MEDIUM

Chemistry>Physical Chemistry>States of Matter>Behaviour of Real Gases

A gas at

350 K

and

15

bar has a molar volume

20

per cent smaller than that for an ideal gas under the same conditions. The correct option about the gas, and its compressibility factor

(Z)

HARD

Chemistry>Physical Chemistry>States of Matter>Behaviour of Real Gases

The above

P - V

diagram represents the thermodynamic cycle of an engine, operating with an ideal mono-atomic gas. The amount of heat, extracted from the source in a single cycle, is:

MEDIUM

Chemistry>Physical Chemistry>States of Matter>Behaviour of Real Gases

The qualitative sketches I, II and III given below show the variation of surface tension with molar concentration of three different aqueous solutions of KCl,

C H_{3} O H

and

C H_{3} {(C H_{2})}_{11} O S O_{3}^{-} N a^{+}

at room temperature. The correct assignment of the sketches is -

Question Image

MEDIUM

Chemistry>Physical Chemistry>States of Matter>Behaviour of Real Gases

A piston filled with 0.04 mol of an ideal gas expands reversibly from 50.0 mL to 375 mL at a constant temperature of

37 . 0^{\circ} C

. As it does so, it absorbs 208 J of heat. The values of q and w for the process will be
(R = 8.314 J/mol K) (ln7.5 = 2.01)

EASY

Chemistry>Physical Chemistry>States of Matter>Behaviour of Real Gases

Calculate the work done during compression of

2

mol of an ideal gas from a volume of

1 m^{3}

10

{dm}^{3}

300 K

against a pressure of

100 kPa

EASY

Chemistry>Physical Chemistry>States of Matter>Behaviour of Real Gases

The work done during combustion of

9 \times 10^{- 2}

kg

of ethane,

C_{2} H_{6} (g)

300 K

is (Given

R = 8 .314 {JK}^{- 1} {mol}^{- 1}

, atomic mass

C = 12, H = 1

)

EASY

Chemistry>Physical Chemistry>States of Matter>Behaviour of Real Gases

The compressibility factor

(Z)

of a gas is

< 1

at STP. Therefore

HARD

Chemistry>Physical Chemistry>States of Matter>Behaviour of Real Gases

For one mole of a van der Waals' gas, the compressibility factor

Z = (\frac{p V}{R T})

at a fixed volume will certainly decrease, if
[Given : " a " and " b " are standard parameters for van der Waals' gas]

HARD

Chemistry>Physical Chemistry>States of Matter>Behaviour of Real Gases

If Z is the compressibility factor, then Van der Waal's equation at low pressure can be written as:

Important Questions on States of Matter

Learn and Prepare for any exam you want !