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Which of the following parameter cannot be estimated by using Born - Haber cycle?

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Important Questions on Thermodynamics

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Chemistry>Physical Chemistry>Thermodynamics>Enthalpies for Different Types of Reactions

An athlete is given $100 g$ of glucose $(C_{6} H_{12} O_{6})$ for energy. This is equivalent to $1800 kJ$ of energy. The $50 %$ of this energy gained is utilized by the athlete for sports activities at the event. In order to avoid storage of energy, the weight of extra water he would need to perspire is $_____g$ (Nearest integer) Assume that there is no other way of consuming stored energy.

Given : The enthalpy of evaporation of water is $45 kJ {mol}^{- 1}$

Molar mass of $C, H & O$ are $12.1$ and $16 g {mol}^{- 1}$ .

EASY

Chemistry>Physical Chemistry>Thermodynamics>Enthalpies for Different Types of Reactions

298 K

, the enthalpy of fusion of a solid

(X)

2.8 kJ {mol}^{- 1}

and the enthalpy of vaporisation of the liquid

(X)

98.2 kJ {mol}^{- 1}

. The enthalpy of sublimation of the substance

(X)

kJ {mol}^{- 1}

is ______. (in nearest integer)

MEDIUM

Chemistry>Physical Chemistry>Thermodynamics>Enthalpies for Different Types of Reactions

The change in enthalpy $[Δ H]$ in ${kJmol}^{- 1}$ for the reaction is $Mg + 2 F \to {MgF}_{2}$

Given: $EA$ of $F = 328 kJ {mol}^{- 1}, {IE}_{1}$ of $Mg = 737 kJ {mol}^{- 1}, {IE}_{2}$ of $Mg = 1451 kJ {mol}^{- 1}$

EASY

Chemistry>Physical Chemistry>Thermodynamics>Enthalpies for Different Types of Reactions

C (s) + O_{2} (g) \to C O_{2} (g), Δ H = - X,

C O (g) + \frac{1}{2} O_{2} (g) \to C O_{2} (g), Δ H = - Y,

Calculate

Δ_{f} H

for

C O_{(g)}

formation

HARD

Chemistry>Physical Chemistry>Thermodynamics>Enthalpies for Different Types of Reactions

Enthalpy of fusion and enthalpy of vaporization for water respectively are

6.01 kJ {mol}^{- 1}

and

45.07 kJ {mol}^{- 1}

0 ° C

what is enthalpy of sublimation at

0 ° C

EASY

Chemistry>Physical Chemistry>Thermodynamics>Enthalpies for Different Types of Reactions

Given

NO (g) + O_{3} (g) \to {NO}_{2} (g) + O_{2} (g) ∆ H = - 198 .9 kJ / mol

O_{3} (g) \to 3 / 2 O_{2} (g) ∆ H = - 142 .3 kJ / mol

O_{2} (g) \to 2 O (g) ∆ H = + 495 .0 kJ / mol

The enthalpy change

(∆ H)

for the following reaction is

N O (g) + O (g) \to N O_{2} (g)

HARD

Chemistry>Physical Chemistry>Thermodynamics>Enthalpies for Different Types of Reactions

The Born-Haber cycle for $KCl$ is evaluated with the following data:
$Δ_{f} H^{Θ} for KCl = - 436.7 {kJmol}^{- 1}; Δ_{sub} H^{Θ} for K = 89.2 {kJmol}^{- 1};$

$Δ_{ionization} H^{Θ} for K = 419.0 kJ {mol}^{- 1}; Δ_{electron gain} H^{Θ} for {Cl}_{(g)} = - 348.6 {kJmol}^{- 1}$

$Δ_{bond} H^{Θ} for {Cl}_{2} = 243.0 {kJmol}^{- 1}$
The magnitude of lattice enthalpy of $KCl$ in ${kJmol}^{- 1}$ is (Nearest integer)

MEDIUM

Chemistry>Physical Chemistry>Thermodynamics>Enthalpies for Different Types of Reactions

The enthalpy change for the conversion of

\frac{1}{2} {Cl}_{2}

(g) to

{Cl}^{-} (aq)

(-)

{kJmol}^{- 1}

(Nearest integer)
Given :

Δ_{dis} H_{{Cl}_{2 (g)}}^{0} = 240 {kJmol}^{- 1}

Δ_{eg} H_{Cl (g)}^{o} = - 350 {kJmol}^{- 1}

Δ_{hyd} H_{{Cl}_{(g)}^{-}}^{o} = - 380 {kJmol}^{- 1}

MEDIUM

Chemistry>Physical Chemistry>Thermodynamics>Enthalpies for Different Types of Reactions

The elements with the highest and the lowest enthalpy of atomisation respectively, for first row transition elements are:

HARD

Chemistry>Physical Chemistry>Thermodynamics>Enthalpies for Different Types of Reactions

For one mole of NaCl(s) the lattice enthalpy is

${Na}_{(s)} + \frac{1}{2} {Cl}_{2} (g) \overset{+ 108.4 kJ / mol}{⟶} {Na}_{(s)} + \frac{1}{2} {Cl}_{2} (g) \overset{+ 495.6 kJ / mol}{⟶} {Na}_{(g)}^{+} + \frac{1}{2} {Cl}_{2} (g) \overset{121 kJ / mol}{⟶}$

${Na}_{(g)}^{+} + Cl (g) \overset{- 348.6 kJ / mol}{⟶} {Na}_{(g)}^{+} + {Cl}_{(g)}^{-} \overset{{ΔH}^{0} altice}{⟶} Nacl$ (solid) $\underset{- 411.2 kJ / mol}{\leftarrow} {Na}_{(s)} + \frac{1}{2} {Cl}_{2} (g)$

EASY

Chemistry>Physical Chemistry>Thermodynamics>Enthalpies for Different Types of Reactions

Given that, the molar combustion enthalpy of benzene, cyclohexane and hydrogen are

x, y

and

z

, respectively, the molar enthalpy of hydrogenation of benzene to cyclohexane is

MEDIUM

Chemistry>Physical Chemistry>Thermodynamics>Enthalpies for Different Types of Reactions

Enthalpy of sublimation of iodine is

24 c a l g^{- 1}

200 ° C

. If specific heat of

I_{2}

(s) and

I_{2}

(vap) are

0.055

and

0.031 c a l g^{- 1} K^{- 1}

respectively, then enthalpy of sublimation of iodine at

250 ° C

c a l g^{- 1}

is:

MEDIUM

Chemistry>Physical Chemistry>Thermodynamics>Enthalpies for Different Types of Reactions

The enthalpy of combustion of propane, graphite and dihydrogen at

298 K

are:

- 2220.0 kJ {mol}^{- 1}

- 393.5 kJ {mol}^{- 1}

and

- 285.8 kJ {mol}^{- 1}

, respectively. The magnitude of enthalpy of formation of propane

(C_{3} H_{8})

is _____

{kJmol}^{- 1}

. (Nearest integer)

MEDIUM

Chemistry>Physical Chemistry>Thermodynamics>Enthalpies for Different Types of Reactions

Given:

(i)

C (graphite) + O_{2} (g) \to {CO}_{2} (g);

{ΔrH}^{Θ} = x kJ {mol}^{- 1}

(ii)

C (graphite) + \frac{1}{2} O_{2} (g) \to CO (g);

{ΔrH}^{Θ} = y kJ {mol}^{- 1}

(iii) CO (g) + \frac{1}{2} O_{2} (g) \to {CO}_{2} (g);

{ΔrH}^{Θ} = z kJ {mol}^{- 1}

Based on the above thermochemical equations, find out which one of the following algebraic relationships is correct?

MEDIUM

Chemistry>Physical Chemistry>Thermodynamics>Enthalpies for Different Types of Reactions

At $25 ° C$ , the enthalpy of the following processes are given:

$H_{2} (g) + O_{2} (g) \to 2 OH (g) Δ H^{o} = 78 kJ {mol}^{- 1}$

$H_{2} (g) + 1 / 2 O_{2} (g) \to H_{2} O (g) Δ H^{0} = - 242 kJ {mol}^{- 1}$

$H_{2} (g) \to 2 H (g) Δ H^{o} = 436 kJ {mol}^{- 1}$

$1 / 2 O_{2} (g) \to O (g) Δ H^{0} = 249 kJ {mol}^{- 1}$

What would be the value of X for the following reaction? (Nearest integer)

$H_{2} O (g) \to H (g) + OH (g) ∆ H^{o} = X {kJmol}^{- 1}$

MEDIUM

Chemistry>Physical Chemistry>Thermodynamics>Enthalpies for Different Types of Reactions

Consider the following data

Heat of combustion of $H_{2} (g) = - 241.8 kJ {mol}^{- 1}$

Heat of combustion of $C (s) = - 393.5 kJ {mol}^{- 1}$

Heat of combustion of $C_{2} H_{5} OH (l)$ $= - 1234.7 kJ {mol}^{- 1}$

The heat of formation of $C_{2} H_{5} OH (l)$ is $(-)$ _____ $kJ {mol}^{- 1}$ (Nearest integer).

MEDIUM

Chemistry>Physical Chemistry>Thermodynamics>Enthalpies for Different Types of Reactions

Given

(A) $2 CO (g) + O_{2} (g) \to 2 {CO}_{2} (g) {ΔH}_{1}^{o} = - x kJ {mol}^{- 1}$

(B) $C (graphite) + O_{2} (g) \to {CO}_{2} (g) {ΔH}_{2}^{o} = - y kJ {mol}^{- 1}$

The $∆ H^{o}$ for the reaction $C (graphite) + \frac{1}{2} O_{2} (g) \to CO (g)$ is

MEDIUM

Chemistry>Physical Chemistry>Thermodynamics>Enthalpies for Different Types of Reactions

The ionization enthalpy of

{Na}^{+}

formation from

{Na}_{(g)}

495.8 kJ {mol}^{- 1},

while the electron gain enthalpy of

Br

- 325.0 kJ {mol}^{- 1}

. Given the lattice enthalpy of

NaBr

- 728.4 kJ {mol}^{- 1}

. The energy for the formation of

NaBr

ionic solid is

(-)_____10^{- 1} kJ {mol}^{- 1}

MEDIUM

Chemistry>Physical Chemistry>Thermodynamics>Enthalpies for Different Types of Reactions

Lattice enthalpy and enthalpy of solution of

NaCl

are

788 {kJmol}^{- 1}

and

4 k J m o l^{- 1}

, respectively. The hydration enthalpy of

N a C l

is:

EASY

Chemistry>Physical Chemistry>Thermodynamics>Enthalpies for Different Types of Reactions

The enthalpy change on freezing of

1 mol

of water at

5 ° C

to ice at

- 5 ° C

is:

(Given

Δ_{fus} H = 6 kJ {mol}^{- 1}

0 ° C,

C_{p} (H_{2} O, l) = 75 .3 J {mol}^{- 1} K^{- 1}

C_{p} (H_{2} O, s) = 36 .8 J {mol}^{- 1} K^{- 1}

)

Which of the following parameter cannot be estimated by using Born - Haber cycle?

Important Questions on Thermodynamics

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