# Thermodynamic Processes

## Trending Questions

**Q.**

What is Gibbs Helmholtz equation? Explain with the help of applications.

**Q.**16 g oxygen gas expands at STP to occupy double of its original volume. The work done during the process is

- -260.2 cal
- 260.2 kcal
- -272.8 cal
- 272.8 kcal

**Q.**

What is entropy and its physical significance?

**Q.**Equal masses of H2, O2 and methane have been taken in a container of volume V at temperature 27oC in identical conditions. The ratio of the volumes of gases H2:O2:CH4 would be

- 8:16:1
- 16:8:1
- 16:1:2
- 8:1:2

**Q.**

Complete the following equation and balance it:

${\mathrm{CO}}_{2}+\mathrm{NaOH}\to $

**Q.**The normal boiling point of water is 373 K. Vapour pressure of water at temperature T is 19 mm Hg. If enthalpy of vaporisation is 40671.40 J/mol, then temperature T would be:

(Use :log2=0.3, R:8.3 JK−1 mo1−1)

- 150.2 K
- 291.3 K
- 330.3 K
- 390 K

**Q.**Why heat is a path function? How can we verify if a quantity is a path function?

**Q.**

State the type of reaction and balance the equation.

${\mathrm{Cl}}_{2}+\mathrm{KBr}\to \mathrm{KCl}+{\mathrm{Br}}_{2}$

**Q.**

The average thermal energy for a mono-atomic gas is (k_{b} is Boltzmann constant and T is absolute temperature)-

**Q.**

Match the thermodynamic processes taking place in a system with the correct conditions. In the table:$\u2206Q$ is the heat supplied, $\u2206W$ is the work done, and$\u2206U$ is the change in internal energy of the system.

A) (I) – (1), (II) – (1), (III) – (2), (IV) – (3)

B) (I) – (1), (II) – (2), (III) – (4), (IV) – (4)

C) (I) – (2), (II) – (4), (III) – (1), (IV) – (3)

D) (I) – (2), (II) – (1), (III) – (4), (IV) – (3)

Column 1 | Column 2 |
---|---|

(I) Adiabatic |
(1)$\u2206W=0$ |

(II)Isothermal |
(2)$\u2206Q=0$ |

(III)Isochoric |
(3)$\u2206U\ne 0,\u2206W\ne 0,\u2206Q\ne 0$ |

(IV)Isobaric |
(4)$\u2206U=0$ |

**Q.**The molar enthalpy of vaporization of hexane (C6H14) is 28.9 kJ/mol, and its normal boiling point is 69∘C. What is the vapour pressure of hexane at 25.00∘C in torr? [e−1.5=0.222]

- 169.5 torr
- 195.4 torr
- 134.6 torr
- 202.2 torr

**Q.**

Action of water on calcium carbide (CaC_{2}) is used for the preparation of acetylene gas (C_{2}H_{2}) used in welding. After the reaction, calcium carbide is converted into slaked lime. Write the balanced equation for the reaction.

**Q.**One mole of an ideal gas is carried through a reversible cyclic process as shown in the figure. The maximum temperature attained by the gas during the cycle is (in K):

- 76R
- 1249R
- 4912R
- None of these

**Q.**A gas is said to behave like an ideal gas when the relation PVT=constant. When do you expect a real gas to behave like an ideal gas

- When the temperature is high and pressure is low
- When both the temperature and pressure are low
- When the temperature is low
- When both the temperature and pressure are high

**Q.**1 mole of NH3 gas at 27 ∘C is expanded in reversible adiabatic condition to make the volume 8 times (γ=1.33). Final temperature and work done respectively are:

- 150 K, −900 cal
- 150 K, −400 cal
- 250 K, −1000 cal
- 200 K, −800 cal

**Q.**Which of the following has the highest reduction potential?

**Q.**One mole of Helium gas undergoes a reversible cyclic process ABCDA as shown in the figure.

Assuming gas to the ideal, answer the following questions:

What is the value of ‘q’ for the overall cyclic process?

- −200R ln 2
- −100R ln 2
- +100R ln 2
- +200R ln 2

**Q.**

Match the thermodynamic processes given below:

Column IColumn IIA. Freezing of water at 273K and 1 atmp. q=0B. Expansion of 1 mole of an ideal gas into a vacuum under isolated conditions q. W=0C. Mixing of equal volumes of two ideal gases at constant temperature and pressure in an isolated containerr. ΔSsys<0D. Reversible heating of H2(g) at 1 atm from 300 K to 600K, followed by reversible cooling to 300K at 1 atms. ΔU=0t. ΔG=0

(A) →r, t; (B) →q, s, t; (C) →p, q, s; (D) →p, q, s

(A) →r, t; (B) →p, q, s; (C) →p, q, s; (D) →q, s, t

(A); →q, s, t(B) →p, q, s; (C) →p, q, s; (D) →r, t

(A) →r, t; (B) →p, q, s; (C) →p, q, s; (D) →q, s, t

**Q.**

The state of a gas can be described by quoting the relationship between

(a) pressure, volume, temperature

(b) temperature, amount, pressure

(c) amount, volume, temperature

(d) pressure, volume, temperature, amount

**Q.**

Which of the following is true for a isobaric process?

dQ = 0

dV = 0

dP = 0

dT = 0

**Q.**Find the E0 value for the reaction,

In2+(aq)+Cu2+(aq)⇌In3+(aq)+Cu+(aq) at 298 K.

Given:

E0Cu2+(aq)/Cu+(aq)=0.15 VE0In2+(aq)/In+(aq)=−0.4 V

E0In3+(aq)/In+(aq)=−0.42 V

- 0.59 V
- 1.23 V
- 0.23 V
- 0.97 V

**Q.**The pressure in the tyre of a car is four times the atmospheric pressure at 300 K. If this tyre suddenly brusts, its new temperature will be :

(γ=1.4)

- 300(4)1.4/0.4
- 300(14)−0.4/1.4
- 300(2)−4/1.4
- 300(4)−0.4/1.4

**Q.**Assertion (A): Liquids tend to have maximum number of molecules at their surface. Reason (R): Small liquid drops have spherical shape.

- Both A and R are true but R is not the correct explanation of A.
- A is false but R is true.
- A is true but R is false.
- Both A and R are true and R is the correct explanation of A.

**Q.**

(Molar specific heat capacity at constant pressure) - (Molar specific heat capacity at constant volume) is equal to:

R

P

V

T

**Q.**The plots between P and V which represent isochoric and isobaric process respectively:

- I, II
- IV, I
- I, IV
- II, III

**Q.**

If a molecule of nitrogen combines with three of hydrogen, how many molecules of ammonia will be formed?

**Q.**

Balance the following equations:

(iii) ${\mathrm{C}}_{2}{\mathrm{H}}_{6}+{\mathrm{O}}_{2}\to {\mathrm{CO}}_{2}+{\mathrm{H}}_{2}\mathrm{O}$

**Q.**What is the work which could be obtained from an isothermal reversible expansion of 1 mol of Cl2 from 1 dm3 to 50 dm3 at 273 K using ideal gas behaviour.

- −8.88 kJ mol−1
- 8.88 kJ mol−1
- −88.8 kJ mol−1
- 88.8 kJ mol−1

**Q.**For a gas solid adsorbent system, the adsorption isotherm xm=kP1n is applicable, where n=5 in the specified case. Point out the correct statement:

- log(xm) vs logP plot is a linear graph with slope equal to 5
- log(xm) vs logP plot is a linear graph with slope equal to 0.2
- (xm) vs P plot is a linear graph with slope equal to 5
- None of these

**Q.**One mole of an ideal gas is subjected to a two-step reversible process (A - B and B - C). The pressure at A and C is the same. Mark the correct statement(s):

- Work done in the path AB is zero
- In the path AB, work will be done on the gas by the surrounding
- VC=3×VA
- VB=16.42 litres