For which change $∆H\ne ∆E$

1. $H_2+I_2\rightleftharpoons 2HI$

2. $HCl+NaOH\to NaCl+H_{2}O$

3. $C\left(s\right)+O_2\left(g\right)\rightleftharpoons C{O}_2\left(g\right)$

4. $N_2+3H_2\to 2N{H}_3$

Enthalpy change when 1.00 g water is frozen at $0^{\circ }C,$ is :

$\left(∆H_{fus}=1.435 kcal mo{l}^{-1}\right)$

1. 0.0797 kcal

2. -0.0797 kcal

3. 1.435 kcal

4. -1.435 kcal

One mole of hydrogen gas at ${25}^{\circ }C$ and 1 atm pressure is heated at constant pressure until its volume has doubled. Given that $C_v$ for hydrogen is 3.0 cal deg^-1 mol^-1, the $∆H$and $∆E$ for this process are-

1. $∆H$= 1490 cal and $∆E$ = 894 cal

2. $∆H$= $∆E$= 1490 cal

3. $∆H$= 894 cal and $∆E$= 1490 cal

4. $∆H$= $∆E$= 894 cal

The enthalpy change of the reaction

$A{l}_{2}C{l}_6\left(s\right)+6Na\left(s\right)\to 2Al\left(s\right)+6NaCl\left(s\right)$ is -257 kcal.

Given the heat of formation of NaCl(s) is -98.0 kcal, the heat of formation of $A{l}_{2}C{l}_6\left(s\right)$ is-

1. 158 kcal

2. -331 kcal

3. -166 kcal

4. 316 kcal

Some of the thermodynamic parameters are state variables while some are process variables. Some grouping of the parameters are given. Choose the correct one-

1. State variables : Temperature, No. of moles

Process variables : Internal energy, work done by the gas

2. State variables : Volume, Temperature

Process variables : Internal energy, work done by the gas

3. State variables : work done by the gas, heat rejected by the gas.

Process variables : Temperature, volume

4. State variables : Internal energy, volume

Process variables : Work done by the gas, heat absorbed by the gas

One mole of a real gas is subjected to heating at constant volume from$\left(P_1, V_1, T_1\right)$ state to $\left(P_2, V_2, T_2\right)$ state. Then it is subjected to irreversible adiabatic compression against constant external pressure of P₃ atm till syatem reaches the final state$\left(P_3, V_3, T_3\right)$. If the constant volume molar heat capacity of real gas is C_V. Find out correct expression for $∆H$ from state 1 to state 3-

1. $C_v\left(T_3-T_1\right)+\left(P_3{V}_1-P_1{V}_1\right)$

2. $C_v\left(T_2-T_1\right)+\left(P_3{V}_2-P_1{V}_1\right)$

3. $C_v\left(T_2-T_1\right)+\left(P_3{V}_1-P_1{V}_1\right)$

4. $C_p\left(T_2-T_1\right)+\left(P_3{V}_1-P_1{V}_1\right)$

The heat evolved in the combustion of 112 litres of water gas(mixture of equal volumes of H₂ and CO) is:

1. 241.8 kJ

2. 283 kJ

3. 1312 kJ

4. 1586 kJ

In which case of mixing of a strong acid and a base, each of 1(N) concentration, temperature-increase is the highest ?

1. 20 ml acid and 30 ml alkali

2. 10 ml acid and 40 ml alkali

3. 25 ml acid and 25 ml alkali

4. 35 ml acid and 15 ml alkali

The heats of neutralisation of four acids A, B, C and D are -13.7, -9.4, -11.2 and -12.4 kcal respectively when they are neutralised by a common base. The acidic character obeys the order :

1. A>B>C>D

2. A>D>C>B

3. D>C>B>A

4. D>B>C>A

The $∆H_f^{\circ }$ for CO₂(g), CO(g) and H₂O(g) are -393.5, -110.5 and -241.8 kJ mol^-1 respectively. The standard enthalpy change (in kJ) for the reaction,

$C{O}_2\left(g\right)+H_2\left(g\right)\to H_{2}O\left(g\right)+ CO\left(g\right)$ is :

1. 524.21

2. 41.2

3. -262.5

4. -41.2