HARD

NEET

IMPORTANT

Earn 100

The enthalpy changes for the following processes are listed below.

${Cl}_{2 (g)} \to 2 Cl (g), ∆ H = 242.3 kJ {mol}^{- 1}$

$I_{2 (g)} \to 2 I_{(g)}, ∆ H = 151.0 kJ {mol}^{- 1}$

${ICl}_{(g)} \to I_{(g)} + {Cl}_{(g)}, ∆ H = 211.3 kJ {mol}^{- 1}$

$I_{2 (s)} \to I_{2 (g)}, ∆ E = 62.76 kJ {mol}^{- 1}$

The standard states of iodine and chlorine are ${I_{2}}_{(s)}$ and ${Cl}_{2 (g)}$ , respectively. What is the standard enthalpy of formation for ${ICl}_{(g)}$ ?

28.57% studentsanswered this correctly

Important Questions on Thermodynamics

MEDIUM

NEET

IMPORTANT

Beta Question Bank for Medical: Chemistry>Chapter 4 - Thermodynamics>EXERCISE-III (Analytical Questions)>Q 14

Consider the reaction,

4 {NO}_{2} (g) + O_{2} (g) \to 2 N_{2} O_{5} (g), ∆_{r} H = - 111 kJ .

N_{2} O_{5} (s)

is formed instead of

N_{2} O_{5} (g)

in the above reaction, the

∆_{r} H

value will be

(Given,

∆ H

of sublimation for

N_{2} O_{5} (s)

is 54

k J m o l^{- 1}

)

HARD

NEET

IMPORTANT

Beta Question Bank for Medical: Chemistry>Chapter 4 - Thermodynamics>EXERCISE-III (Analytical Questions)>Q 15

For complete combustion of ethanol, $C_{2} H_{5} OH (l) + 3 O_{2} (g) ⟶ 2 {CO}_{2} (g) + 3 H_{2} O (l)$ , the amount of heat produced as measured in bomb calorimeter, is $1364.47 kJ {mol}^{- 1}$ at $25 ° C$ . Assuming ideality the enthalpy of combustion, $Δ_{C} H$ reaction will be :

$(R = 8.314 kJ {mol}^{- 1})$

MEDIUM

NEET

IMPORTANT

Beta Question Bank for Medical: Chemistry>Chapter 4 - Thermodynamics>EXERCISE-III (Analytical Questions)>Q 16

If the bond dissociation energies of

XY, X_{2} & Y_{2}

(all diatomic molecules) are in the ratio

1 : 1 : 0.5

and

∆ H_{f}

for the formation of

XY

- 200 kJ {mol}^{- 1}

, the bond dissociation energy of

X_{2}

will be

MEDIUM

NEET

IMPORTANT

Beta Question Bank for Medical: Chemistry>Chapter 4 - Thermodynamics>EXERCISE-III (Analytical Questions)>Q 17

The standard enthalpy of formation

(∆ H_{f}^{o})

298 K

for methane,

C H_{4} (g) i s - 78.4 k J {m o l}^{- 1}

. The additional information required to determine the average energy for

C - H

bond formation would be

HARD

NEET

IMPORTANT

Beta Question Bank for Medical: Chemistry>Chapter 4 - Thermodynamics>EXERCISE-III (Analytical Questions)>Q 18

The standard enthalpy of formation of NH₃ is -46 kJ mol^-1 . If the enthalpy of formation of H₂ from its atoms -436 kJ mol^-1 and that of N₂ is - 712 kJ mol^-1 , the average bond enthalpy of N - H bond in NH₃ is :

MEDIUM

NEET

IMPORTANT

Beta Question Bank for Medical: Chemistry>Chapter 4 - Thermodynamics>EXERCISE-III (Analytical Questions)>Q 19

Oxidising power of chlorine in an aqueous solution can be determined by the parameters indicated below:

$\frac{1}{2} {Cl}_{2} (g) \overset{\frac{1}{2} Δ_{dis} H^{⊖}}{⟶} Cl (g) \overset{Δ_{eg} H^{⊖}}{⟶} {Cl}^{-} (g) \overset{Δ_{hyd} H^{⊖}}{⟶} {Cl}^{-} (aq)$

The energy involved in the conversion of

$\frac{1}{2} {Cl}_{2} (g)$ to ${Cl}^{-} (aq)$

(using the data, $Δ_{diss} H_{{Cl}_{2}}^{⊖} = 240 kJ {mol}^{- 1}$ , $Δ_{eg} H_{Cl}^{⊖} = - 349 kJ {mol}^{- 1}, Δ_{hyd} H_{{Cl}^{-}}^{⊖} = - 381 kJ {mol}^{- 1}$ ) will be:

MEDIUM

NEET

IMPORTANT

Beta Question Bank for Medical: Chemistry>Chapter 4 - Thermodynamics>EXERCISE-III (Analytical Questions)>Q 20

On the basis of the following thermochemical data:

${ΔH}_{f} ° (H_{aq}^{+}) = 0$

$\begin{array}{l} H_{2} O (l) \to H^{+} (aq) + {OH}^{-} (aq); ΔH ° = 57.32 kJ \\ H_{2} (g) + \frac{1}{2} O_{2} (g) \to H_{2} O (l); ΔH ° = - 286.20 kJ \end{array}$

The value of the enthalpy of formation of ${OH}^{-}$ ions at $25 ° C$ is:

HARD

NEET

IMPORTANT

Beta Question Bank for Medical: Chemistry>Chapter 4 - Thermodynamics>EXERCISE-III (Analytical Questions)>Q 21

For a spontaneous reaction the

Δ G^{0}

, equilibrium constant (

K

) and

E_{cell}^{0}

will be respectively:

Important Questions on Thermodynamics

Learn and Prepare for any exam you want !