Second Law of Thermodynamics

An engine operating between the boiling and freezing points of water will have

A. Efficiency more than $27\%$.

B. Efficiency less than the efficiency of a Carnot engine operating between the same two temperatures.

C. Efficiency equal to $27\%$.

D. Efficiency less than $27\%$.

Choose the correct answer from the options given below

A flask containing $1 \mathrm{mol} {\mathrm{N}}_2$ at $4 \mathrm{atm}$. and $298 \mathrm{K}$ was connected to a flask containing $1 \mathrm{mol}$ ${\mathrm{N}}_2$ gas at $2 \mathrm{atm}$ and $298 \mathrm{K}$. The gases were allowed to mix isothermally, determine the entropy change for the system:

For an increase in the entropy define ____ of nature.

Which of the following option are correct for the second law of thermodynamics?

The cause of irreversibility of a natural process is:

Causes of irreversible process.

Heat cannot by itself flow from a body at lower temperature to a body at higher temperature” is a statement or consequence of

Mention the causes for irreversibility of a process.

Graphs below show the entropy versus energy $U$ of two systems $1$ and $2$ at constant volume. The initial energies of the systems are indicated by $U_{1, i}$ and $U_{2, i} ,$ respectively. Graphs are drawn to the same scale. The systems are then brought into thermal contact with each other. Assume that, at all times the combined energy of the two systems remains constant. Choose the most appropriate option indicating the energies of the two systems and the total entropy after they achieve the equilibrium.

When $1 \mathrm{kg}$ of ice at $0 °\mathrm{C}$ melts to water at $0 °\mathrm{C}$, the resulting change in its entropy, taking latent heat of ice to be $80 \mathrm{cal} {\mathrm{g}}^{-1}$, is,

The change in entropy when a $30 \mathrm{g}$ ice cube at $-12°\mathrm{C}$ is transformed into water at $100°\mathrm{C}$ $($in $\mathrm{J}/\mathrm{K})$ is

$($Take $\ell \mathrm{n}\left(\frac{273}{261}\right)=0.04; \ell \mathrm{n}\left(\frac{373}{273}\right)=0.312$, ${\mathrm{S}}_{\mathrm{ice}}=2100 \mathrm{J}/\mathrm{kg}-{}^{\circ }\mathrm{C},$$\left.{\mathrm{S}}_{\text{water}}=4200 \mathrm{J}/\mathrm{kg}-{}^{\circ }\mathrm{C}, {\mathrm{L}}_{\mathrm{f}}=3.33\times {10}^5 \mathrm{J}/\mathrm{kg}\right)$

Clausius's statement is a part of

A refrigerator operates on:

One mole of ideal monoatomic gas is taken along a cyclic process as shown in the figure. Process
1 → 2 shown is 1/4^th part of a circle as shown by dotted line process 2 → 3 is isochoric while
3 → 1 is isobaric. If efficiency of the cycle is n% where n is an integer. Find n.

One mole of an ideal monatomic gas undergoes the following four reversible processes:
Step $1 :$ It is first compressed adiabatically from volume $V_1$ to $1 {\mathrm{m}}^2.$
Step $2 :$ then expanded isothermally to volume $10 {\mathrm{m}}^3$
Step $3 :$ then expanded adiabatically to volume $V_3$
Step $4 :$ then compressed isothermally to volume $V_1.$ If the efficiency of the above cycle is $\frac{3}{4}$ then $V_1$ is

What is the entropy change in $J{K}^{-1}$ during the melting of 27.3 g of ice of $0^{o}C$ ? (Latent heat of fusion of ice = 330 $J{g}^{-1}$ )

Choose the incorrect relation among these

According to the third law of thermodynamics which one of the following quantities for a perfectly crystalline solid is zero at absolute zero?

In the following a statement of Assertion is followed by a statement of Reason.

Assertion: During free expansion of an ideal gas, its entropy increases but work done by the gas is zero.

Reason: During free expansion, volume increases but temperature remains constant.