For given following equations and $∆\mathrm{H}°$ values determine the enthalpy of reaction at 298 K for the reaction

C2H4(g) + 6F2(g) $\to$ 2CF4(g) + 4HF(g)

H2(g) + F2(g) $\to$ 2HF(g)       $∆{\mathrm{H}}_{1}^{°}$= -537 kJ

C(s) + 2F2(g) $\to$CF4(g)         $∆{\mathrm{H}}_{2}^{°}$=-680 kJ

2C(s) + 2H2(g) $\to$C2H4(g)    $∆{\mathrm{H}}_{3}^{°}$= 52 kJ

(1) -1165

(2) -2486

(3) +1165

(4) +2486

Concept Questions :-

Enthalpy and It's Type
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

If $∆{\mathrm{H}}_{\mathrm{f}}^{°}$(C2H4) and $∆{\mathrm{H}}_{\mathrm{f}}^{°}$(C2H6) are x1 and x2 kcal/mol then heat of hydrogenation of C2H4 is :-

(1) x1 + x2

(2) x1 - x2

(3) x2 - x1

(4) x1 + 2x2

Concept Questions :-

Thermochemistry
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

For oxidation of iron, 4Fe(s) + 3O2(g) $\to$2Fe2O3(s), $∆{\mathrm{H}}_{\mathrm{r}}^{°}$=-1648x103 J mol-1 entropy change is:

-549.4 J k-1mol-1 at 298 K:-

The reaction is

(1) Spontaneous

(2) Non spontaneous

(3) At Equilibrium

(4) Can't predict

Concept Questions :-

Spontaneity and Entropy
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

18 g of ice is converted into water at 0$°$C and 1 atm. The entropy of H2O(s) and H2O(l) are 38.2 and 60 J K-1 mol-1 respectively. the enthalpy for this conversion will be

(1) 5951.4 J/mol

(2) 595.14 J/mol

(3) -595.14 J/mol

(4) None of these

Concept Questions :-

Gibbs Energy Change
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

One mole of methanol when burnt in O2 gives out 723 kJ mol-1 heat. If one mole of O2 is used, what will be the amount of heat evolved?

1. 482 kJ               2. 241 kJ

3. 723 kJ               4. 924 kJ

Concept Questions :-

Thermochemistry
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

If the bond energies of H-H, Br-Br, and H-Br are 433, 192 and 364 kJ mol-1 respectively,

the $∆\mathrm{H}°$ for the reaction

H2(g) + Br2(g) $\to$2HBr(g) is

1.  -103 kJ               2. -261 kJ

3. +103 kJ               4. +261 kJ

High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

What will be the standard enthalpy of reaction for the following reaction using the listed enthalpies of reaction:-

3Co(s) + 2O2(g)$\to$Co3O4(s);       $∆\mathrm{H}$=?

2Co(s) + O2(g) $\to$2CoO(s)          $∆{\mathrm{H}}_{1}$= -475.8 KJ

6CoO(s) + O2(g) $\to$2Co3O4(s)     $∆{\mathrm{H}}_{2}$ = -355.0 KJ

(1) -891.2 KJ

(2) -120.8 KJ

(3) 891.2 KJ

(4) -830.8 KJ

Concept Questions :-

Enthalpy and It's Type
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

At 25$°$C, for the process H2O(l)$⇌$H2O(g);

$∆\mathrm{G}°$ is 8.6 kJ. The vapour pressure of water at this temperature is nearly:-

(1) 24 torr

(2) 285 torr

(3) 32.17 torr

(4) 100 torr

Concept Questions :-

Spontaneity and Entropy
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

For isothermal expanison in case of an ideal gas:-

(1) $∆$G=$∆$S

(2) $∆$G=$∆$H

(3) $∆$G=-T$∆$S

(4) None of these

Concept Questions :-

Spontaneity and Entropy
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

The free energy change $∆\mathrm{G}$=0 when:-

(1) the system is at equilibrium