Chemical Thermodynamics MCQs for NEET — Chemistry Questions with Answers

Predict which of the following reaction(s) has a positive entropy change?

(i) Ag⁺ (aq) + Cl^-(aq) $\to$AgCl(s)

(ii) NH₄Cl(g) $\to$NH₃(g) + HCl(g)

(iii) 2NH₃(g)$\to$N₂(g) + 3H₂(g)

When two moles of an ideal gas (Cp, m=$\frac{5}{2}$R) heated from 300 K to 600 K at constant pressure the change in entropy of gas ($∆\mathrm{S}$) is:-

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

For isothermal expanison in case of an ideal gas:-

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

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

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

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

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 :-

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

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