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Among the following the number of state variables is ____________ .
Internal energy \( (U) \)
Volume \( (V) \)
Heat \( (q) \)
Enthalpy \( (H) \)

At \( 25^{\circ} \text{C} \) and \( 1 \) \( \text{atm} \) pressure, the enthalpies of combustion are as given below:

The enthalpy of formation of ethane is:

$2\text{O}_3\text{(g)} \rightleftharpoons 3\text{O}_2\text{(g)}$

At $300\text{ K}$, ozone is fifty percent dissociated. The standard free energy change at this temperature and $1\text{ atm}$ pressure is $(-)\ \underline{\quad\quad\quad\quad}\ \text{J mol}^{-1}$. (Nearest integer)

$\left[\text{Given : } \ln 1.35 = 0.3 \text{ and } R = 8.3\text{ J K}^{-1}\text{ mol}^{-1}\right]$

For complete combustion of methanol
\( \mathrm{CH_3OH(l)} + \frac{3}{2}\mathrm{O_2(g)} \rightarrow \mathrm{CO_2(g)} + 2\mathrm{H_2O(l)} \)
The amount of heat produced as measured by bomb calorimeter is \( 726 \, \text{kJ mol}^{-1} \) at \( 27^\circ \mathrm{C} \). The enthalpy of combustion for the reaction is \( -x \, \text{kJ mol}^{-1} \), where \( x \) is _______________. (Nearest integer)
(Given: \( R = 8.3 \, \text{J K}^{-1}\text{mol}^{-1} \))

The enthalpy of combustion of propane, graphite and dihydrogen at \( 298 \, \text{K} \) are \( -2220.0 \, \text{kJ mol}^{-1} \), \( -393.5 \, \text{kJ mol}^{-1} \) and \( -285.8 \, \text{kJ mol}^{-1} \) respectively. The magnitude of enthalpy of formation of propane \( (\mathrm{C_3H_8}) \) is _______ \( \text{kJ mol}^{-1} \). (Nearest integer)

\( \mathrm{C}(s) + \mathrm{O_2}(g) \rightarrow \mathrm{CO_2}(g) + 400\,\text{kJ} \)
\( \mathrm{C}(s) + \dfrac{1}{2}\mathrm{O_2}(g) \rightarrow \mathrm{CO}(g) + 100\,\text{kJ} \)
When coal of purity \( 60\% \) is allowed to burn in presence of insufficient oxygen, \( 60\% \) of carbon is converted into ‘\( \mathrm{CO} \)’ and the remaining is converted into ‘\( \mathrm{CO_2} \)’. The heat generated when \( 0.6 \, \text{kg} \) of coal is burnt is ________.

The standard entropy change for the reaction
\( 4\mathrm{Fe}(s) + 3\mathrm{O}_2(g) \longrightarrow 2\mathrm{Fe}_2\mathrm{O}_3(s) \) is \( -550 \, \text{J K}^{-1} \) at \( 298 \, \text{K} \).
[Given : The standard enthalpy change for the reaction is \( -165 \, \text{kJ mol}^{-1} \).] The temperature in \( \text{K} \) at which the reaction attains equilibrium is __________. (Nearest Integer)

While performing a thermodynamics experiment, a student made the following observations.
\( \mathrm{HCl} + \mathrm{NaOH} \rightarrow \mathrm{NaCl} + \mathrm{H_2O} \) \( \Delta H = -57.3 \, \text{kJ mol}^{-1} \)
\( \mathrm{CH_3COOH} + \mathrm{NaOH} \rightarrow \mathrm{CH_3COONa} + \mathrm{H_2O} \) \( \Delta H = -55.3 \, \text{kJ mol}^{-1} \)
The entropy of ionization of \( \mathrm{CH_3COOH} \) as calculated by the student is ________ \( \text{kJ mol}^{-1} \). [Nearest integer]

\( 2.4 \, \text{g} \) coal is burnt in a bomb calorimeter in excess of oxygen at \( 298 \, \text{K} \) and \( 1 \, \text{atm} \) pressure. The temperature of the calorimeter rises from \( 298 \, \text{K} \) to \( 300 \, \text{K} \). The enthalpy change during the combustion of coal is \( -x \, \text{kJ} \, \text{mol}^{-1} \). The value of \( x \) is __________. (Nearest Integer)
(Given: Heat capacity of bomb calorimeter \( 20.0 \, \text{kJ} \, \text{K}^{-1} \). Assume coal to be pure carbon)

Question 1 of 9Next →

JEE Main 2022 28th July Evening shift

Among the following the number of state variables is ____________ .
Internal energy \( (U) \)
Volume \( (V) \)
Heat \( (q) \)
Enthalpy \( (H) \)