Chemical Thermodynamics MCQs for NEET — Chemistry Questions with Answers

The gas absorbs 100 J heat and is simultaneously compressed by a constant external pressure of 1.50 atm from 8 lit. to 2 lit. in volume. Hence $∆E$ will be-

If $∆G=∆H-T∆S$ and $∆G=∆H+T{\left(\frac{d\left(∆G\right)}{dT}\right)}_P$ then variation of EMF of a cell E, with temperature T, is given by

The standard heat of combustion of Al is -837.8 kJ mol^-1 at ${25}^{\circ }C$ which of the following releases 250 kcal of heat ?

$C_P-C_V=R$. This R is :

Heat of neutralisation of oxalic acid is -25.4 K cal mol^-1 using strong base, NaOH. Hence enthalpy change of the process is $H_2{C}_2{O}_4\rightleftharpoons 2H^{+}+C_2{H_4}^{2-}$is-

During the isothermal mixing of ideal gases at pressure, p, the entropy change per mole for the mixing process is-R $\sum x_i \ln x_i$ where x₁, x₂,....,x_i are the mole fractions of the components, 1, 2,....,i of the mixture. Assuming ideal gas behavior, calculate $∆S$ for the mixing of 0.8 mole of N₂ and 0.2 mole of O₂.(at ${25}^{\circ }C$ and 0.9 atm) [1 eu = cal/deg]

For the reaction : $$\begin{gathered} X_2{O}_4\left(l\right)\to 2X{O}_2\left(g\right) \\ ∆E=2.1 kcal. ∆S=20 cal/K at 300 K. Hence ∆G is : \end{gathered}$$

Heat of hydrogenation of ethene is x₁ and that of benzene is x₂. Hence resonance energy is-

$$\begin{gathered} C_2{H}_6\left(g\right)+3.5O_2\left(g\right)\to 2C{O}_2\left(g\right)+3H_{2}O\left(g\right) \\ ∆S_{vap}\left(H_{2}O, l\right)=x_1 cal K^{-1}\left(b.p. +T_1\right) \\ ∆H_f\left(H_{2}O, l\right)=x_2; ∆H_f\left(C{O}_2\right)=x_3, ∆H_f\left(C_2{H}_6\right)=x_4 \\ Hence ∆H for the reaction is- \end{gathered}$$

The bond energies of$C\equiv C$, C-H, H-H and C=C are 198, 98, 103 and145 kcal respectively. The enthalpy change of the reaction $HC\equiv CH+H_2\to C_2{H}_4$ is