The temperature of 5 ml of a strong acid increases by $5^{\circ }$ when 5 ml of a strong base is added to it. If 10 ml of each is mixed, temperature should increase by-

1. $5^{\circ }$

2. ${10}^{\circ }$

3. ${15}^{\circ }$

4. cannot be known

The heat of neutralisation of HCl by NaOH is -55.9 kJ/mole. If the heat of neutralisation of HCN by NaOH is -12.1 kJ/mole, then energy of dissociation of HCN is-

1. -43.8 kJ

2. 43.8 kJ

3. 68 kJ

4. -68 kJ

Identify the correct statement for a system at equilibrium:
1. ΔG = ΔG° = 0
2. ΔG = 0, but ΔG° ≠ 0
3. ΔG° = 0, but ΔG ≠ 0
4. ΔG = ΔG° ≠ 0

Using only the following data:

(I) $F{e}_2{O}_3\left(s\right)+3CO\left(g\right)\rightleftharpoons 2Fe\left(s\right)+3C{O}_2\left(g\right);$
$∆H^{\circ }=-26.8<mspace\; width="1em"></mspace>kJ$

(II) $$\begin{gathered} Fe\left(s\right)+C{O}_2\left(g\right)\rightleftharpoons FeO\left(s\right)+CO\left(g\right); \\ ∆H^{\circ }=+16.5<mspace\; width="1em"></mspace>kJ \end{gathered}$$

the $∆H^{\circ }$ value, in kilojoules, for the reaction

$F{e}_2{O}_3\left(s\right)+CO\left(g\right)\to 2FeO\left(s\right)+C{O}_2\left(g\right)$ is calculated to be:

1. -43.3

2. -10.3

3. +6.2

4. +10.3

82 litres of carbon dioxide are produced at a pressure of 1 atm by the action of acid on a metal carbonate. The work done at room temperature by the gas (in calories) in pushing back the atmosphere is: 

1. 1000

2. 820

3. 1640

4. 2000

Among the following, the reaction for which $∆H=∆E$ is-

1. $PC{l}_5\left(g\right)\to PC{l}_3\left(g\right)+C{l}_2\left(g\right)$

2. $H_2\left(g\right)+C{l}_2\left(g\right)\to 2HCl\left(g\right)$

3. $C_2{H}_{5}OH\left(l\right)+3O_2\left(g\right)\to 2C{O}_2\left(g\right)+3H_{2}O\left(l\right)$

4. $C_2{H}_4\left(g\right)+H_2\left(g\right)\to C_2{H}_6\left(g\right)$

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 :

$\left(∆H_{fus}=1.435<mspace\; width="1em"></mspace>kcal<mspace\; width="1em"></mspace>mo{l}^{-1}\right)$

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 $∆H<mspace\; width="1em"></mspace>$and $∆E$ for this process are-

1. $∆H<mspace\; width="1em"></mspace>$= 1490 cal and $∆E$ = 894 cal

2. $∆H<mspace\; width="1em"></mspace>$= $∆E$= 1490 cal

3. $∆H<mspace\; width="1em"></mspace>$= 894 cal and $∆E$= 1490 cal

4. $∆H<mspace\; width="1em"></mspace>$= $∆E$= 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