Entropy and Second Law of Thermodynamics

Unit of entropy is:

$2 \mathrm{mol}$ of an ideal gas at  $27°\mathrm{C}$ temperature is expanded reversibly from $2 \mathrm{L}$ to $20 \mathrm{L}$. Find the entropy change. $\left(\mathrm{R}=2 \mathrm{cal}/\mathrm{mol} \mathrm{K}\right)$    

The adsorption of a gas at the boiling point of the gas follows the isotherm shown in the figure. Identify the correct thermodynamic properties at point $C.$

A heat engine absorbs heat ${\mathrm{Q}}_1$ at temperature ${\mathrm{T}}_1$ and heat ${\mathrm{Q}}_2$ at temperature ${\mathrm{T}}_2$. Work done by the engine is $\left({\mathrm{Q}}_1+{\mathrm{Q}}_2\right) \mathrm{J}$. This data

For which of the following processes, $∆\mathrm{S}$ is negative?

The molar heat capacity (${\mathrm{C}}_{\mathrm{p}}$) of ${\mathrm{CD}}_2\mathrm{O}$ is $10 \mathrm{cal}$ at $1000\mathrm{K}$. The change in entropy associated with cooling of $32\mathrm{g}$ of ${\mathrm{CD}}_2\mathrm{O}$ vapour from$1000\mathrm{K}-100\mathrm{K}$ at constant pressure will be : ($\mathrm{D}$ = deuterium, Atomic mass = $2$) 

The enthalpy of vaporization of water at $100°\mathrm{C}$ is $40.63 {\mathrm{kJmol}}^{-1}$. Its entropy of vaporization would be

The $\mathrm{SI}$ unit of $∆\mathrm{S}$ is 

Calculate the melting point of $\mathrm{KCl}\left(\mathrm{s}\right)$ from the data, ${∆}_{\mathrm{fus}}\mathrm{H}\left(\mathrm{KCl}\right)=7.25 \mathrm{kJ} {\mathrm{mol}}^{-1}$ and ${∆}_{\mathrm{fus}}\mathrm{S}\left(\mathrm{KCl}\right)=7 \mathrm{J} {\mathrm{K}}^{-1} {\mathrm{mol}}^{-1}$.

What is the sign of $∆\mathrm{S}$ for the following reaction?

${\mathrm{CaCO}}_3\left(\mathrm{s}\right)\stackrel{ }{\to }\mathrm{CaO}\left(\mathrm{s}\right)+{\mathrm{CO}}_2\left(\mathrm{g}\right)$

What does entropy measure?

For the reaction, ${\mathrm{Fe}}_2{\mathrm{O}}_3\left(\mathrm{s}\right)+3\mathrm{CO}\left(\mathrm{g}\right)\stackrel{ }{\to }2\mathrm{Fe}\left(\mathrm{s}\right)+3{\mathrm{CO}}_2\left(\mathrm{g}\right); ∆{\mathrm{H}}^{\circ }=-28.4 \mathrm{kJ}$ at $298 \mathrm{K}$. Calculate the change in entropy.

Write any two applications of 'second law of thermodynamics'.

A container is divided into two compartments by a removable partition as shown below:

In the first compartment, ${\mathrm{n}}_1$ moles of ideal gas He is present in a volume ${\mathrm{V}}_1.$ In the second compartment, ${\mathrm{n}}_2$ moles of ideal gas $\mathrm{Ne}$ is present in a volume ${\mathrm{V}}_2.$ The temperature and pressure in both the compartments are $\mathrm{T}$ and $\mathrm{P},$ respectively. Assuming $\mathrm{R}$ is the gas constant, the total change in entropy upon removing the partition when the gases mix irreversibly is:

The change in entropy at equilibrium is 

Define entropy and write its $\mathrm{SI}$ unit.

The enthalpy of vaporization of water at $100°\mathrm{C}$ is $40.63 {\mathrm{kJmol}}^{-1}$. Its entropy of vaporization would be