The bond dissociation enthalpy of gaseous H₂, Cl₂ and HCl are 435, 243 and 431 kJ mol^-1, respectively. Calculate the enthalpy of formation of HCl gas.

1. -92 kJ mol^-1

2. -82 kJ mol^-1

3. -21 kJ mol^-1

4. -55 kJ mol^-1

The enthalpy of formation of CO₂(g), H₂O(l) and propene (g) are -393.5, -285.8, and 20.42 kJ mol^-1 respectively. The enthalpy change for the combustion of cyclopropane at 298 K will be:

(The enthalpy of isomerization of cyclopropane to propene is -33.0 kJ mol^-1. )
1. -1021.32 kJ mol^-1
2. -2091.32 kJ mol^-1
3. -5021.32 kJ mol^-1
4. -3141.32 kJ mol^-1

From the following data of $∆H$, of the following reactions,

$C\left(s\right)+\frac{1}{2}{O}_2\to CO\left(g\right) ;∆H=-110 kJ$
$C\left(s\right)+H_{2}O\to CO\left(g\right)+H_2\left(g\right) ;∆H=132 kJ$

What is the mole composition of the mixture of steam and oxygen on being passed over coke at 1273 K, keeping temperature constant.

1. 0.5 : 1

2. 0.6 : 1

3. 0.8 : 1

4. 1 : 1

Which of the following thermodynamic quantities is an outcome of the second law of thermodynamics?

1. Work

2. Enthalpy

3. Internal energy

4. Entropy

The molar entropy of the vapourization of acetic acid is\(14.4~ \mathrm{cal}~ \mathrm{K}^{-1} \mathrm{~mol}^{-1}\) at its boiling point ${118}^{\circ }C$. The latent heat of vapourization of acetic acid is-

$$\begin{gathered} {\mathrm{C}}_2{\mathrm{H}}_6\left(\mathrm{g}\right)+3.5{\mathrm{O}}_2\left(\mathrm{g}\right)\to 2{\mathrm{CO}}_2\left(\mathrm{g}\right)+3{\mathrm{H}}_2\mathrm{O}\left(\mathrm{g}\right) \\ ∆{\mathrm{S}}_{\mathrm{vap}}\left({\mathrm{H}}_2\mathrm{O}, \mathrm{l}\right)={\mathrm{x}}_1 \mathrm{cal} {\mathrm{K}}^{-1}\left(\mathrm{b}.\mathrm{p}. +{\mathrm{T}}_1\right) \\ ∆{\mathrm{H}}_{\mathrm{f}}\left({\mathrm{H}}_2\mathrm{O}, \mathrm{l}\right)={\mathrm{x}}_2; ∆{\mathrm{H}}_{\mathrm{f}}\left({\mathrm{CO}}_2\right)={\mathrm{x}}_3, ∆{\mathrm{H}}_{\mathrm{f}}\left({\mathrm{C}}_2{\mathrm{H}}_6\right)={\mathrm{x}}_4 \\ \mathrm{Hence} ∆\mathrm{H} \mathrm{for} \mathrm{the} \mathrm{reaction} \mathrm{is}- \end{gathered}$$

1. $2x_3+3x_2-x_4$

2. $2x_3+3x_2-x_4+3x_1{T}_1$

3. $2x_3+3x_2-x_4-3x_1{T}_1$

4. $x_1{T}_1+x_2+x_3-x_4$

Which of the following statements is correct with regard to $∆$G of a cell reaction and EMF of the cell (E) in which the reaction occurs ?

(1) Both $∆$G and E are extensive properties

(2) $∆$G is an intensive property but E is an extensive property

(3) $∆$G is an extensive property and E is an intensive property

(4) Both $∆$G and E are intensive properties.

The bond energies of C=C and C-C at 298 K are 590 and 331 kJ mol^-1 respectively. The enthalpy of polymerization per mole of ethylene is

1. -70 kJ

2. -72 kJ

3. 72 kJ

4. -68 kJ

Enthalpy of fusion of a liquid is 1.435 kcal mol^-1 and molar entropy change is 5.26 cal mol^-1K^-1. Hence melting point of liquid is :

1. ${100}^{\circ }C$

2. $0^{\circ }C$

3. 373 K

4. $-{273}^{\circ }C$

For the reaction, $2{\mathrm{N}}_2\left(\mathrm{g}\right)+{\mathrm{O}}_2\left(\mathrm{g}\right)\to 2{\mathrm{N}}_2\mathrm{O}\left(\mathrm{g}\right)$, at 298K $∆\mathrm{H}$ is 164 kJ mol^-1. The $∆\mathrm{E}$ of the reaction is-
1. \(166.5 \mathrm{~kJ} \mathrm{~mol}^{-1} \)
2. \(141.5 \mathrm{~kJ} \mathrm{~mol}^{-1} \)
3. \(104.0 \mathrm{~kJ} \mathrm{~mol}^{-1} \)
4. \(-169 \mathrm{~kJ} \mathrm{~mol}^{-1}\)