The $∆H_f^{\circ }$ for CO₂(g), CO(g) and H₂O(g) are -393.5, -110.5 and -241.8 kJ mol^-1 respectively. The standard enthalpy change (in kJ) for the reaction,

\(\mathrm{CO}_2 \mathrm{~(g)}+\mathrm{H}_2 \mathrm{~(g)} \rightarrow \mathrm{H}_2 \mathrm{O~(g)}+\mathrm{CO}(g)\) is :

1. 524.21

2. 41.2

3. -262.5

4. -41.2

The bond dissociation energy of CH₄ and C₂H₆ are 360 and 620 Kcal/mole respectively. Determine the bond enthalpy of a single carbon-carbon (C–C) bond:

1. 260 Kcal/mole

2. 180 Kcal/mole

3. 130 Kcal/mole

4. 80 Kcal/mole

For an endothermic reaction :
1. \(\sum H_{\text {Products }} =\sum H _{\text {Reactants }} \)
2. \(\sum H_{\text {Products }} <\sum H_{\text {Reactants }} \)
3. \(\sum H_{\text {Products }} >\sum H_{\text {Reactants }} \)
4. \(\sum H_{\text {Products }} =0~ \text {but }\sum H _{\text {Reactants }} \text { is positive.}\)

Which of the following statements correctly describes the change in entropy of the universe during all natural processes?

1. A decrease in entropy of the universe
2. An increase in entropy of the universe
3. No change in entropy of the universe
4. Sometimes an increase and sometimes a decrease in entropy of the universe

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. \(-169 \mathrm{~kJ} \mathrm{~mol}^{-1}\)

Find the temperature range at which the reaction A → B becomes spontaneous.

Given:

ΔH = +4 kcal mol⁻¹
ΔS = +10 cal mol⁻¹ K⁻¹

1. 400 K
2. 300 K
3. 500 K
4. None of the above

44.0 kJ of heat is required to evaporate one mole of water at 298 K. If $∆H_f$ of $H_2\mathrm{O(}\left(l\right)$ ) is -286 kJ mol^-1, $∆{H^{\circ }}_f$ of $H_{2}O\left(g\right)$ is:

1. -330 kJ mol^-1

2. +242 kJ mol^-1

3. -242 kJ mol^-1

4. -198 kJ mol^-1

The correct calculate value for $△H$ for:

$\mathrm{M}\left(\mathrm{s}\right)<mspace\; width="1em"></mspace>\to {\mathrm{M}}^{2+}\left(\mathrm{aq}\right)$

From following arbitrary values : 

$\mathrm{M}\left(\mathrm{s}\right)<mspace\; width="1em"></mspace>\to \mathrm{M}\left(\mathrm{g}\right)<mspace\; width="1em"></mspace>;△\mathrm{H}<mspace\; width="1em"></mspace>=<mspace\; width="1em"></mspace>1000\mathrm{KJ}<mspace\; width="1em"></mspace>{\mathrm{mol}}^{-1}$
$\mathrm{M}\left(\mathrm{g}\right)<mspace\; width="1em"></mspace>\to {\mathrm{M}}^{+}\left(\mathrm{g}\right)<mspace\; width="1em"></mspace>;<mspace\; width="1em"></mspace>△\mathrm{H}<mspace\; width="1em"></mspace>=<mspace\; width="1em"></mspace>750\mathrm{KJ}<mspace\; width="1em"></mspace>{\mathrm{mol}}^{-1}$
${\mathrm{M}}^{+}\left(\mathrm{g}\right)\to {\mathrm{M}}^{2+}\left(\mathrm{g}\right);△\mathrm{H}<mspace\; width="1em"></mspace>=<mspace\; width="1em"></mspace>1200\mathrm{KJ}<mspace\; width="1em"></mspace>{\mathrm{mol}}^{-1}$
${\mathrm{M}}^{2+}\left(\mathrm{g}\right)+\mathrm{aq}<mspace\; width="1em"></mspace>\to {\mathrm{M}}^{2+}(\mathrm{aq}.);<mspace\; width="1em"></mspace>△\mathrm{H}<mspace\; width="1em"></mspace>=<mspace\; width="1em"></mspace>-1800\mathrm{KJ}<mspace\; width="1em"></mspace>{\mathrm{mol}}^{-1}$

1. 1950 KJ mol^-1 

2. 1150 KJ mol^-1 

3. 2300 KJ mol^-1 

4. None of the above.

The molar heat capacity, $C_v$ of an ideal gas whose energy is that of translational motion only is

1.  $2.98<mspace\; width="1em"></mspace>J<mspace\; width="1em"></mspace>de{g}^{-1}mo{l}^{-1}$

2. $12.47<mspace\; width="1em"></mspace>J<mspace\; width="1em"></mspace>de{g}^{-1}mo{l}^{-1}$

3. $6.43<mspace\; width="1em"></mspace>J<mspace\; width="1em"></mspace>de{g}^{-1}mo{l}^{-1}$

4. $9.41<mspace\; width="1em"></mspace>J<mspace\; width="1em"></mspace>de{g}^{-1}mo{l}^{-1}$

The enthalpy of hydration of Na⁺(g) and Cl^-(g) ions are -406 kJ mol^-1 and -364 kJ mol^-1 respectively.
The enthalpy of the solution of NaCl(s) is:
\(\text{The lattice energy of NaCl is}~ 780~{ kJ mol}^{-1}. \)

1. 23 kJ mol^-1

2. 10 kJ mol^-1

3. -10 kJ mol^-1

4. -82 kJ mol^-1